I think talking to them at community centers might be a good learning experience.

I think talking to them at community centers might be a good learning experience. You can also feel free, I think, to say hello to homeless people you see on the street, ask them how they are doing, see if they need water or food, or just if they want to talk. A lot of people treat homeless people like they are invisible, so being seen and treated like a human can be really helpful, and might be informative to you as well.