I Am A 78-year-old Male Who Has Had One Heart

I am a 78-year-old male who has had one heart attack, stopped by quick insertion of three stints, and a second very minor attack a year later (2015). This year I have had restricted physical activity due to diabetic foot problems. I weighed 300 lbs for several years then dropped to 250 about three years ago. Now I have regained ten lbs and am having a hard time losing it again. I am wondering about the "free testosterone" products as a way of helping lose weight and increasing my energy level, What would you suggest?