Medical Assistance

I have some medical issued that I cannot afford to fix. Three in particular. I have cataracts that's so bad I cannot drive at night, and kidney or colon problem that I think may be cancer. The sad part I'd I have a good job. I can't wait much longer on the cataracts. And the other problems are beginning to scare me. Is there a doctor that would be willing to at least donate a diagnosis on the kidney/colon problem?