Does literature ever stop going over your head? I fear that everything

No.
That's why people study it.

My brain is fucking weird, in that I read something, I remember none of it, I'm tested on it, I still remember none of it, and yet 9 years later somebody will ask me a question and I'll just spontaneously refer to some shit. Its made me excellent at Trivia and relatively shit at Testing.

Anyways, if you want to memorise things better OP, the techniques are well known, largely as a result of techniques developed for language learning. If I really have to memorise something I'll make flashcards and review them with spaced repetition. Maybe I'll just jot down some notes in the margin instead. It's just fucking dull and 95% of books I don't care enough to do it and figure I get more value out of reading more books than reading the same ones repeatedly.
For the other 5% I don't note take to the extent I would if I was actually studying for grades.

>>9974354
That's literally how brains work. "Name all the books you've read." is difficult for a brain to process. "Have you read this book?" isn't.

>>9974167
Someone might suggest How to Read and Why by Bloom, but that wouldn't help. He doesn't tell you '''''how'''''' to read, he just recites a passage from a book and says "hmm yes this is good" and sometimes explains why, but he doesn't show you how he extracted any of his observations, he just says them.

So don't read that book with the intention of it making you smarter.

Still worth a read tho, imo.