According to my personal situation, breakfast 10*30=300, lunch 20*30=600 and dinner 15*30=450. Plus 1500 If roommates get together for dinner on weekends, it will be enough to buy some clothes and fruits for school, and the school meals are also cheap, so we can eat enough in about 3-5 yuan, depending on the individual.
If the family situation is better, it is recommended to be around 2000-300. Schools also have part-time jobs, and they can also take part-time jobs when there are no classes. A part-time job in the canteen is to manage meals, which can save a lot of money in a month. Anyway, it depends on the individual. 3000 can eat enough, and 500 can eat enough. Do what you can according to the situation.