Good lord do you eat anything other than fast food?
If money is a problem then going somewhere to eat/get take away is the worst choice.
You can eat home cooked meals for days at the price of that stuff (to be fair I know it's cheaper in America(I'm assuming you're there))
A bag of frozen veggies, some chicken and a stir fry sauce can make a meal big enough to last you at least 2 days, is easy as 123 and cheap as hell.
Trust me your situation isn't as bad as you think it is, both because you can get by with that much money and because I'm sure your dad is able to handle it, as he will have done many, many times in the past (the only difference is you knowing about it)
Above all else remember that the amount of food you regularly eat is far more than enough, you don't need 3 meals a day and constant snackage to get by. Just don't eat so much (double point, your stomach shrinks anyway so you wouldn't want as much food as before)
My parents were pretty lower-mid class earners, coupled with having 5 children hunger was something that happened sometimes, if there was no food there was no food, pretty simple. Lived anyway.
On the bracketed topic of shrunken stomachs, if you haven't experienced it much before you'd be surprised how little you want to eat. After living in the Philippines I couldn't eat more than half a sandwich every day or two, it was great.
My stomach is tiny right now and trust me it saves money.
The funny thing is that now I could go buy out a whole shopping aisle and feast like a king, yet I still go days without food because I cbf going to the shop to buy some.
