I think I've seen The Godfather, start to finish. Maybe once. Have never seen II or III.
I actually haven't seen the 2nd or 3rd LOTR movies, despite reading the books at age ~13, and then re-reading them in college when they started making the movies. Haven't seen the Hobbit. Haven't watched the 2nd or 3rd Matrix movies. I've seen Star Wars 1, 4-6, 7-9, Solo, and Rogue One. I've vaguely seen bits and pieces of movies 2 and 3 when the kids were watching them, but have never sat through them straight through.
I don't watch a lot of movies, tbh...