When House of the Dragon premiered, Game of Thrones fans weren't sure what to expect. As the first of many planned spinoffs to the supremely popular series and an equally widespread distaste for the later seasons, audiences were skeptical if House of the Dragon would pan out. Luckily, audiences and critics alike were enthralled by the series based on George R.R. Martin's prequel book, Fire & Blood. When adapting a book to the big or small screen, changes need to be made, but often, book fans don't receive these changes well. In House of the Dragon, the changes made to the overall story expanded upon the original tale perfectly and showed the writers had done their homework. Many are even of the opinion that these changes improved the story.
Source：https://www.cbr.com/house-of-the-dragon-improved-the-original-story/
