Help with medical expences

This was the last thing I wanted to do but rt now I feel I have no choice. I have Large  Bcell Non-Hodgkins Lymphoma . and need to be able to get back and forth to Drs appointments. My car has had it I have put $500 in to it this week alone and still cant get to my appointment tomorrow.  If you cant help please share. I don't know what else to do.