How are you all eating?

Hi guys! I’m student teaching high school and have been for about a month so far, which means that I’m trying to get into a routine that’s reasonably healthy for myself without burning out (lol). Part of that is trying to fix up my lunches: I’ve been bringing a bagel with cream cheese for lunch for the last month and it’s not working for me. I don’t want to have to microwave any food because I only have nonmicrowavable tupperware. So how are you guys eating, any tips for me to pack something that’ll keep me going?