What should I do about this?

Hey snap I'm a vegetarian too ^-^
I decided to become vegetarian at around 9 years old. Luckily my parents were fine with it amd respected my opinions, and gave me meat substitutes instead, like quorn, nuts, vegetarian sausages, burgers, chicken etc..

As for your situation, its quite difficult because you say you can't get your own food. I totally understand that your dad isn't being helpful, so you'll have to sit down with him and the rest of the family where possible and talk it over, because he probably thinks its just a phase.
Try not to be too rebellious and don't say 'refuse' and 'you cant force me' and so on, be really calm and super nice and explain that either way you are not going to eat meat, because you don't like it and you would feel much better and more relieved if they could respect that.
don't forget to big it up and say how stressed it is making you, and you could even throw in the fact that you had to ask for help on the internet, this will really hit home with your parents and hopefully persuade them that you are serious that you don't want to eat meat, and you need their help to get the right nutritions.

You will probably have to compromise, like maybe eating fish or saying 'maybe on day i will consider eating meat again' even if you have no intention of that. either way, you will have to think carefully about this whole thing. you could talk to a trusted teacher about it at school, or go onto the internet and research help for beginner vegetarians.

Hope you do ok hun, keep me posted how you get on and let me know if you need any more advice ^-^ x
Lottey x

Just don't eat the meat. *sigh* sorry I'm not helpful, but I'm not a fan of vegetarians, especially the ones who don't eat meat because animals are harmed, and no I'm not some cruel heartless person, it's just PETA people never even bother to actually know what's going on, for instance if deer aren't hunted they overpopulate and die of diseases and starvation, who wants to let some poor animal starve to death because there's too much competition for food?

Well, see if you can have a formal talk with him, tell him why you don't want meat and ask nicely for him to get you food without meat.
My parents have always been supportive so this is only sort of a guess.