I have avascular necrosis in both my talus' can't exercise much. how can i lose weight fast to help get pressure off my feet?

Low carb diet.: This is the fastest way of losing weight if adhered to. Combining this with weight training will really help. Do avoid uncessary fats when possible and get plenty of fiber and fluids!

Water therapy: It would probably have to involve exercises that don't put a lot of load on the feet. Exercises in the water would be idea, you can burn a lot of calories and become quite conditioned, but would not have as much stress on your feet. Thank you for the question.