Figure out how much you need in calories a day. (bmr)
Then subtract 500 calories from that. That will have you losing 1 pound a week.
Any exercise is weight lost on top of that. 500 calories burned a day extra is another pound a week lost.
You can tweak the calories/exercise as needed/tolerated.
I have heard up to 3 pounds a week is considered healthy weight loss.
Good luck!