The noon time is short. As long as the hunger problem is solved, the school canteen is a good choice. It is best to stir-fry at home. You don't have to have big fish and big meat, otherwise you will be sleepy in the afternoon.
It can be a little better at night, with some fish and meat. If you study late, you can prepare some snacks and fruits to cushion your hunger.
But be clear! It is not enough for parents to cook three meals a day! Make him happy! Never let him feel that you are a parent, like a friend! Note that it is to make him "feel like", for example, don't worry too much, for example, talk to him more when he wants to talk, for example, play with him more and make a noise, which is the most important thing!
Finally, I wish your children progress in their studies!
-home cooking is fine (don't tell me you can't cook, then go to the bookstore and buy a cookbook). In fact, home cooking can fully meet the nutritional requirements of children, and he will eat whatever you eat.