The series diverged from the books massively some to e ago. There are key characters for whom very different paths are being followed in the books.
That’s why it will be interesting to see whether the critical story beats remain the same, but the journey is a different route, or the whole thing is different.
I read the books way back when they first came out, but my wife is refusing to read them until they are done, as she can’t tolerate the concept they might not get finished.
Unless you are not a book person, you really should read them. They are superior to the series in many ways and a fantastic story in their own right.