I think I started watching Game of Thrones around the fourth season (my wife gave me the cliffs notes), so I’ve missed a bunch, but I’ve seen enough now where I have to know what happens from here on out. For those deeper into it, here’s a comparison between the books and the television series by Alyssa Karla Mungcal, Jocelyn Tan, and Pooja Sharma.
The above is an overview, but they also break it down by scene, marking each as matching with the book or not.