When it comes to weight loss, what percentage of work needed is food related and what percentage is exercise related?

Different Approach. Weight loss is not "food related or exercise related". It is the sum total of energy in and energy out. When you exercise, you use up energy (burn calories). When you eat, you store energy (consume calories). If you take any more than you burn up, you gain weight. Without cutting some calories, it is difficult to lose a significant amount of weight.
Calorie restriction. For most americans weight loss is best achieved with calories restriction rather than just exercise. Studies show that when trying to lose weight the optimal amount of exercise is 150 min/week. More than that leads to overeating and to many calories consumed to lose one pound per week, decrease your calories by 500 per day. Your body becomes more efficient with less food.