The one I am most familiar with is the Harry Potter series. I love the books and the movies. I think each is good in its own. While they are not identical, there was enough overlap to appreciate the movies after having read the books.
I have read several that have been book to movie. The Twilight series for example, I feel the books were better, but the two were different. I started the Sookie Stackhouse series by Charlene Harris (True Blood TV series) on my old device (Nook) but it was stolen. The books were absolutely different but since I did not get far before device was stolen, I can't say which I prefer. I will need to download the books again to finish reading.
I'd like to recommend two movies that have left a lasting impression on me. Firstly, "The Darkest Minds" offers a captivating storyline that, surprisingly, I found even more engaging than the original books. Despite being somewhat lesser-known, it's a hidden gem worth discovering. Also, "The Hate U Give" deserves special recognition for its ability to allow the viewer to empathize so deeply with the experiences of the characters. This film not only offers a beautifully executed cinematic experience but also delivers a powerful message about social justice. I personally enjoyed the book and movie equally.