Where can someone who can no longer take care of themselves find a place to live?

Bless you for advocating for your friend! Yes, as suggested by WorriedinCali he may need to apply for Medicaid, so there is a solution. He needs to call, research, act asap (Texas' Agency on Aging, sometimes called the Council on Aging, for resources and info) and you may be needed to help him fill out the application that can be downloaded at his county's DHS website, if that's where this all goes.

Since your friend is sick & disabled and cannot work, he should contact Texas health and human services as well as apply for social security disability ASAP. He’s under 60 but he might also benefit from contacting the local area on aging for a needs assessment and they can tell him what services he qualifies for.

Check this link

https://www.agingcare.com/local/assisted-living