I have a friend who is a chronic diabetic, how can he get health insurance , he is very poor.

It depends on where he lives. The city I live in has a Department of Public Health with an office that is run very much like a typical doctor's office. People that can't afford to pay go there for treatment. Sometimes the wait is a little longer but the care is good.

Call your local Social Service office, explain the situation and ask what his options are.