But at this time they have no income because they are trying to get there SSI. Can they live with me without affecting there SSI. And will it affect my disability check that I am drawing now.
You are a good friend and are risking that friendship by opening your home. Any relationship is difficult at times. Do yourself and your friend a huge favor and discuss the minutia as even the smallest thing can blow up when the bloom is off the rose. Regardless of the SSI issues you would be very foolish to think things won't go wrong at times. Are you now a landlord? A co-tenant? Be careful that you don't create a problem for down the road. You say "they" so is this a couple? What happens if one of them passes? Are you now the caretaker of the other? I'm not suggesting you don't help your friend, I'm just imagining what could happen. I hope it's all blue sky and you enjoy having others in your space.
https://www.medicare.gov/coverage/home-health-services.html