Hi im dr.hema physiotherapist.
You should start with low intensity exercises ,As soon as your body strength returns to normal conditions, you may increase the intensity over time.
It is normal to have extra bulk in your stomach after
appendix surgery and if you crossed your healing process that is it may take 6 weeks , start with low intensity exercise like sitting and slowly lifting your legs so it is parallel to ground, tuck ins to abdominals.
Reduce weight if needed.(if age and weight is appropriate)
Take healthy diet- A proper balanced diet-
Avoiding unhealthy food.
Eat lot of fruits and vegetables, this will not only reduce hunger but also add to the bulk of the food.skimmed dairy products, take fresh salad after lunch and dinner like cucumber, tomatoes with curd.
Reduce salt intake.
Avoid high calorie food like fries, pizza, sweets and others.
Hope the information is useful.do reply in doubt.