I think for you, it will be mainly about your nutrition(like it is for everybody, in reality). Listen to your doctors and physical therapists for your exercise and activity advice. Do what they ask you to do. They will help you heal properly.
To lose weight, you may want to speak with a nutritionist to evaluate your current nutritional habits and recommend changes. Have you ever tracked what you eat or kept a food journal? That would be a good place to start... check out the sticky threads in this forum, too. Look closely at the ones about nutrition.