First of all, it's right for you to control your diet like this, but it's wrong for you to lose fat without losing your chest. You have to cooperate with exercise. If you want to reduce calorie intake, you can eat 2-3 slices of whole wheat bread, drink a glass of milk or add a fruit if it is not enough in the morning. This can ensure the nutrition in the morning. You ate right at noon, but don't add any food. You can add a little if you want to exercise. You can eat a carrot at night. This is very thin. Or a plate of vegetarian dishes, to ensure normal defecation, but also to avoid being too hungry to eat at night.

PS: Keep 35CC/ kg of water every day, which is the reasonable way to drink water.

So 1 month can see the effect, 7-8 kg is no problem.