start exercising and eating healty

I use too be very active before I got hurt. Now that I have permanent nerve damage and had 2 surgeries on my back. I have given up alot of my normal activies. Being that my doctor says I have permanent damage and can never do anything more than light duty if that. So instead of cooking my meals I eat fast food alot. I need to do more homecooked meals and at least walk around the block once after supper 3 to 5 days a week.