/lit/ - Literature

I have always wanted to be part of some lore community. I wanted to read source material for something that is big with geek communities. I really enjoyed reading Andrzej Sapkowski, but I only read one book.
A few years ago I picked up reading 40k books. I didn't feel overwhelmed by the fact that there is 60 of them and still coming out. I read ''Horus Rising'' and it was amazing. I loved this book and I still think Loken was great character. But I was reading it, and it introduced Mournival, it started referring to other primarchs. With second book introducing the other primarch as well as high ranking space marines in their chapters.. and I just got so overwhelmed by all these characters.
My initial goal was to be knowledgeable on the lore. But I don't remember 4/5 of the characters from the books.
I got all the way to 5th book Fulgrim, I read it and I just don't want to continue anymore. Reading /tg/, I feel like it will only get worse because the lore will start to get inconsistent.

Am I just adhd sperg who can't remember characters or are these novels really overrated?
I feel like I want to stick with fiction books that have MAX 3 books in the series, so I can actually follow the characters. Thinking of reading Dune now. Is that a good idea?