It's technically a work of fiction but The Dispossessed by Ursula Le Guin can maybe be considered an anarchist book. It does a deep delve into an anarchist society and how it could theoretically be organized. In my opinion it could also be interpreted as a critique, but I think it's stronger for it.

There's plenty, and they can help, but you ain't gotta read em. They're guides and ideas. Nobody ever told me I needed to read Proudhon to think the state's bad, and usually older texts become more of historical interest than theory interests. When I wanted to understand anarchism I was told to go out and engage in praxis.

Being on the receiving end of crowd control munitions is certainly a better education then any book.

If you're curious about theory there's tons of alternatives to books: podcasts, film, public speeches, community training/workshops, etc.

My suggestion is Women's War by Robert Evans on Behind the Bastards. I also suggest pretty much anything on https://channelzeronetwork.com/

If someone just shows up and participates with an open mind they're doing more than most. Anyone who would gatekeep because you didn't read such and such text should be promptly told to fuck right off because that's a caustic hierarchical bullshit appeal to false authority and kills engagement.

If you need a (text)book try The Ecology of Freedom - Bookchin. You could probably find other books here too https://theanarchistlibrary.org/library/murray-bookchin-the-ecology-of-freedom

V for Vendetta?