Help with weight loss and taking prednisone

I am desparate. I am a 46 yr old asthmatic. I've been on prednisone and a list of other steroids so long that I've gained over 75 lbs. I don't know what to do because the excess weight is beginning to impede by overall health like an increase in my blood pressure. sore knees. Obesity runs in my family but feel with my asthma I am heading to an early grave.

I need help please.