How much should I expect to spend every month living on campus at mac?

Hi! My dad is really worried about things I might need while I’m on res. He’s wondering, aside from dorm, tuition, and meal plan that we’re already paying through osap, will I need to spend some more money on top of that? And not just like textbooks or something, but other additional cost that I’m not aware of? What is a reasonable amount of money to have on hand, $300 a month? Or would you say less or more?

Please let me know thanks!