Weight loss help please?

Well, I want to try to lose about 85 to 90 pounds so I can be around my ideal weight for my height, which I believe is 125-140 or something like that. The thing is though, I am limited with what I can do. There isn't a whole lot of healthy stuff in the house because well, it is just more expensive and my mom only gets paid once a month, so often, much of the money goes to bills. I weigh 215 right now and I am 5'3" I want to try to lose the weight over the summer but I live in Florida and it is soooo hot and humid outside. It makes it hard to breathe because I have asthma. My chest starts to hurt too, I have inflammed joints by my sternum. So I am kind of in a bad position. Plus, I live in the middle of nowhere, so there isn't anything near by. Like parks and gyms and that stuff. So what can I do? I would like to at least be close to my goal by the end of the summer. I have 2 months and three weeks just about from today to lose the weight. I appreciate the help.