At what level can I start reading simple texts?

I’m not in a position to give advice, but you can start reading N5 material level 10 and when you’ve learned N5’s grammar (I recommend Bunpro).

Here’s a good recourse .

You’re very right. There are book clubs here that read together and discuss the grammar/story. There’s even an absolute beginners book club Absolute Beginners Book Club // Reading Next: Miss Shikimori is not just cute!