This is crazy me with crazy differences.
I am going to post the difference between the show and the books of the first season, first episode.
The TV series starts with three rangers of the Night’s Watch going beyond the Wall. In the book, they have already been ranging for days.
In the book, the White Walker attack happens after several days of riding North of the Wall, but in the TV series it happens in a forest close to the Wall on the same day the rangers leave Castle Black.
The White Walkers are mostly called Others in the books, especially by the people of the Seven Kingdoms. It is the wildlings that refer to them as ‘White Walkers’.
In the TV series, Will discovers the wildlings massacred and their bodies brutalized. In the book, he says they appeared to be sleeping and likely froze to death.
The White Walkers are of different appearance in the TV series. In the book, they have white skin and reflective light armor. In the TV series, they have frozen grey skin, dark hair, and a brutal face similar to a skull. They don’t seem to wear any armor.
In the TV series, Gared and Waymar Royce face the White Walkers’ first attack, while Will is exploring the area. In the book, Gared is left a short distance away to protect the horses and Will is climbing a tree to get a visual on the wildlings while Waymar Royce was left beneath the tree to face the White walkers alone.
In the book, a group (at least five) of “the Others” (White Walkers) approach Ser Waymar Royce, who has a duel with one of them before finally being killed by the group. In the TV series not more than two White Walkers appear, and Waymar is killed in a surprise attack by one.
The wight girl, who frightens Will in the series is never mentioned in the book.
In the book, Ser Waymar Royce is transformed into a wight.
In the TV series, Gared is the second one to be killed by the White Walkers and Will escapes. In the books, Will is strangled by the wight of Ser Waymar Royce and Gared escapes but is later executed by Ned for desertion. There is a key difference in the fact that in the TV series the death is a beheading at the hands of a White Walker as opposed to being killed by a wight.
The Winterfell soldiers’ capture of Will is not described in the book.
There are several additional scenes in the TV series, taking place in Winterfell, which introduce the Stark family. Bran is shown practicing archery, while his father is watching him. The scene with needlework, which involves Sansa and Arya, is moved to the beginning of the series, before King Robert arrives. In the book, the scenes in Winterfell begin with the deserter’s execution.
Arya is shown to be an accurate archer, while in the books, she doesn’t know how to fire a bow and wishes she could learn. She has not shot a single arrow in any of the books.
In the book, Theon Greyjoy kicks the severed head of the executed deserter, which disgusts Jon Snowwho is later revealed to have never liked Theon anyway. In the TV series, Theon does not kick the severed head of the executed deserter and he is shown to be on good terms with Jon before they part ways.
In the books, between the execution of the deserter and the discovery of the direwolf pups, Robb and Jon have a riding race; this is omitted in the TV series.
Events of the TV series are seventeen years after Robert’s Rebellion. The books begin fourteen years after, thus the Stark children are visibly older. Robb and Jon Snow are 17 instead of 14 (turning 15). Branis 10 instead of 7 and Rickon’s age is increased from 3 to 6.
The Stark girls’ birth years are altered to Sansa 13 instead of 11 (turning 12) and Arya is 11 instead of 9.
Likewise, the Royal children are older: Joffrey is 16 instead of 12, Myrcella is 11 instead of 8 and Tommen is 10 instead of 7.
Daenerys is 16 instead of 13 (turning 14).
In the book, snow covers the grounds around Winterfell. In the TV series, there is no snow.
In the book, the direwolf pups were also found in waist-deep snow.
The scene in King’s Landing introducing Queen Cersei and her brother Jaime is not in the books. It also shows the corpse of Jon Arryn.
In the book, Daenerys Targaryen is introduced, after Eddard Stark gets the news about Jon Arryn’s death. In the TV series, she appears after the scene at Lyanna Stark’s tomb.
Targaryens have violet eyes in the books but this trait was dropped from the series. The showrunners have said that they did use purple contacts early in filming, but this interfered with the actor’s performance as emotion is conveyed through the eyes.
Illyrio Mopatis’s appearance is different to his description in the books. In the series, Illyrio is overweight and has dark brown hair flecked with grey with a forked beard. In the books, Illyrio is described as being morbidly obese with gold, oiled hair and a forked yellow beard.
Khal Drogo’s appearance is slightly different to his description in the books. He is described as having long mustachios with rings in them and many bells in his long braid. In the series, he has a beard with a single ring in it and does not have bells in his hair.
In the book, Daenerys, Viserys and Illyrio go to Khal Drogo’s manse in Pentos and attend a party there to celebrate Drogo and Daenerys’s engagement. Many people appear in this party, including guests from other Free Cities; several other khals; also, this party is where Ser Jorah is first seen. In the series, Khal Drogo simply rides up to Illyrio’s manse with his bloodriders to assess Daenerys.
Tyrion Lannister’s appearance is different to his description in the books. He is described as having stunted legs, a swollen forehead, a squashed-in face and eyes of different colors. He walks with a profound waddle.
In the book, the arrival of the royal party is described from Eddard’s point of view, thus the following scenes in the series are not present in the books: Catelyn and Luwin preparing for the feast; Robb, Theon and Jon preparing themselves for the arrival of the royal party; Bran sighting the royal party on the top of the wall; Catelyn scolding Bran for climbing up the wall; Arya watching the arrival of the royal party; House Stark and their retainers lining up to greet the royal party and Arya’s whimsy.
In the book, the wheelhouse of Queen Cersei and the royal children is very huge, as the book goes, it is “pulled by forty heavy draft horses” and “too wide to pass through the castle gate”; thus the queen has to debark outside and walk into the castle. In the series, the wheelhouse is much smaller and is pulled by lesser horses into the castle.
Tyrion’s introduction in the books is different. He is introduced at the feast through the eyes of Jon Snow. In the TV series, he is introduced in a scene with Ros after Robert Baratheon’s arrival.
In the book, Robert visits Lyanna’s tomb (guided by Eddard) first, and then requests Eddard to be his Hand of the King. In the TV series, he does these two things in reversed order.
There’s an additional conversation between Catelyn and Sansa, which introduces Sansa and her personality. In books she is only briefly described at the feast and her personality is shown at the Trident.
The entrance of the Royal Family and House Stark to the feast, described in the book, was omitted in the TV series.
In the book, Benjen Stark enters the feast along with the Royal Family and the other members of House Stark; in the TV series he arrives late, after the feast begins.
In the TV series, Jon Snow doesn’t attend the feast at all. He meets his uncle Benjen outside, when he is practicing with a sword. In the book, he attends the feast but is not permitted to sit at the main table with the royal family. Instead, he sits near the back with the squires, but is actually pleased with this as, out of sight, he is free to drink as much wine as he pleases (and gets drunk as a result). As the book goes, this feast is among the few times “when Jon Snow was glad he was a bastard”. Then Benjen approaches him and they have their conversation inside the feasting hall.
In the book, the description of the feast is from Jon’s point of view, thus it focuses on the conversation between Jon and Benjen, and that of Jon and Tyrion; and the scenes depicting the activities of other people in the feast are mostly not present in the book – these include King Robert’s activities and Queen Cersei’s reactions; conversation between Benjen and Eddard; conversation between Catelyn and Cersei; conversation between Jaime and Eddard about tournaments; Sansa speaking to the queen and Arya throwing food at Sansa, etc.
Lysa’s letter isn’t coded in the TV series and came by a messenger. In the book it is coded, found in a box with a false bottom, and was left in Maester Luwin’s room by an unknown party.
Production images revealed that the prop letter actually was written in a symbolic code invented for the TV series, but this plot point was omitted in the final version of the episode (apparently to simplify the narrative for TV-first viewers). In the final version, the camera never actually sees what is written on the letter, only Catelyn’s reaction.
Daenerys and Khal Drogo’s wedding scene is shown earlier in the TV series than in the book. Ser Jorah Mormont is introduced in this scene rather than in Daenerys’ first scene.
Jorah Mormont’s appearance is different, in the books, he is described as bald, stocky, hairy, and unattractive, but is strong and fit. In the series, he has short blond hair and is leaner and more attractive.
In the book, Catelyn Stark encourages Ned to accept King Robert’s request. In the TV series, she is afraid for him and begs him not to accept.
In the book, Eddard plans to take Bran to King’s Landing, before he is injured. There is no mention of this in the episode.
In the book, Cersei and Jaime talk about the previous events that transpired with the former Hand, Jon Arryn. This discussion instead takes place in the scene showing Jon Arryn’s corpse.
In the book, Jaime pushes Bran from the window with his right hand. In the show he uses his left hand.
Thank You for reading!
I get information about such things from Game of Thrones Wikia, you guys can check the site out if you want to know more detailed things.
I update about the second episode if get enough response.
Thank you Again!!