As a big fan of FNaF, I don't blame you! That movie is ... rough! haha
For anyone who isn't into FNaF already, but wants to do the "homework" for each house, I'd honestly recommend the 2014 FNaF1 Markiplier playthrough on Youtube over the film itself!
It's a silly thing to say, especially for those who weren't ever into Youtube Let's Play content from that era, but if you're willing to stick with it, that series shows off everything from the first game, and most everything that made FNaF the series as big as it is today. Mark's pretty charismatic, and that specific playthrough was ground zero for a good majority of the FNaF fandom. Besides the Afton stuff, I believe seeing that first game will give you a very solid foundation going into the house this year.