Yayyy I’m excited about this question 
What is Anarchism? was my intro to anarchism. I just read it to understand what my friends were talking about and be able to speak their language so they would listen to me. Turned out the reason they wouldn’t listen to me was because they’re manarchists, but the book was very convincing!
“To Change Everything” is a really good short intro. Also Crimethinc has many other great zines.
prole.info is great. I think I’ve only read The Housing Monster but seriously so good.
Resonance Audio Distro has a bunch of fantastic stuff, especially great because they offer a multitude of listening/reading formats so you can pick what suits best. And they link to even more resources.
The Anarchist Library can be really great if you’re looking for a specific topic or article or author (or want to make your own collections for zines!), and you can also shuffle and read, but I really wouldn’t recommend that as an intro bc it gets pretty wild.
There’s like, lots of stuff, and like, I’m still not sure I totally understand exactly where the line even is between communist and individualist strains, etc. but you could probably be set for a good few months of reading materials if you end up liking the above resources 