literally just fix homelessness
Dude, I know everyone makes it out to be a simple thing, but it's really absolutely not. Homelessness and mental health issues are associated...usually a combination of addiction with one or more other mental illnesses that are severely disabling...be it PTSD, schizophrenia, etc. It is absolutely not as simple as just "give everyone some money" or "give everyone a place to live". Obviously that sort of stuff helps way a lot, but it is really not the easy fix people think it is. Many of these people even end up wandering away from housing that is given to them exactly because of their multiple overlapping severe mental illnesses.
Basically, the majority of homeless people are also severely disabled by often multiple overlapping mental illnesses which are difficult to treat even in people with stable housing. We should always always strive to find them food and shelter, but it is NOT the easy fix that people think it is. It's a multi-layered issue that requires an insane amount of different types of resources.