I Am A 61 Year Old Female. My 5 Coronary

I am a 61 year old female. My 5 coronary artery bypass was done in 2005. I am not in bad physical shape but I am overweight and can not seem to lose weight, Current 235 lbs and I am 5ft 3inches. I also have scaring of the lower lobes of my lungs due to BOOP from 2006. I am at my wits end. I can not seem to get any answers. Please help if you can.
Thank You,
JoAnn