Foundational recommendations for someone who was born yesterday

Hey all! Bit of a different request but this year I’m on a mission to educate myself in mythology, lore and things I have otherwise missed. Backstory: I was raised in a cult. I never learned about dinosaurs or any history predating Jesus, my history and science lessons were “biblical” (I only found out that women and men have the same amount of ribs a few years ago). I never encountered Greek mythology or really anything that communicated the spirituality of other cultural groups.

I’ve been reading a lot and have enjoyed the journey of learning through reading. I’ve been focusing a lot on classics and philosophy but I really enjoy fantasy and think there is validity to incorporating books I would have been banned from reading.

So. What fantasy titles do you consider to be foundational? Classics? What fantasy titles do you think do a good job of portraying different cultures and belief systems/modes of spirituality. I’d love to hear your suggestions!