What is the best way for someone who's confined to a wheelchair and obese to try and lose weight?

Calorie focus + h2o: If in a wheelchair, it is critical to focus on calorie restriction. Of course, water-based exercise is always encouraged, but not always available. If morbidly obese (bmi over 35), then weight loss surgery is worth considering.

Obesity mobility: Complicated question. Losing weight is always a combination of an appropriate diet and exercise plan. Taking in less intake in calories could be achieved by a doctor supervised weight loss plan. Or, better than that, an evaluation and plan by a dietician. The exercise part is a little more complicated and would depend on what types of exercise you could perform to increase your metabolism.