Well, the broad strokes will be "spoiled" for you reading the book. But there are plenty of events left to the show to do whatever they want. The book is not "written" but GRRM per se. It's transcribed from a text by Archmaester Gyldayn a generation or two after the Dance.

He himself is working off of conflicting sources. So there are plenty of moments where something happens, say that Criston Cole plainly hates Rhaenyra. As to why there are three conflicting stories. What's an adaptation going to do...? So even though one has read the book, there are plenty of surprises to be had.