It sounds to me like you're bored, because it can trick your brain into thinking you're hungry when actually you're not. Also if you're just sat around all day you're most likely to crave sugar or chocolate because that gives you a quick kick to wake you up, which you don't need if you live an active lifestyle, you'd need protein. (Of course everyone needs protein and sugar etc but with energy release in food and an active lifestyle protein and carbs are best)
Obviously exercising is better and much healthier but if you want to loose weight you can't just "diet" because that's when people end up putting the weight back on and more, to loose weight and be happy and for it to stay off there needs to be a lifestyle change - which includes what you eat, where you eat, who you eat with, when you eat and the same applies for exercise because these can effect even though it sounds stupid.
What do you mean "my health is messed up"? What's wrong with you, other than you don't exercise and eat healthy? Do you have some medical condition that needs treatment?
It's easy to start exercising... all you have to do is get up and go for a walk... A brisk 30 minute walk most days of the week is an excellent place to start. Or if you have a bicycle, you can ride bike, go swimming, join a yoga or zumba class or do any type of sport/exercise that interests you. Or just exercise on your own. The biggest thing is get up and get moving... even sweeping/vacuuming/mopping the floors and helping your parents around the house, doing yard work, etc are exercise...
As far as food is concerned, you will need to enlist the help of your parents or whoever does the grocery shopping in your house. They will need to make sure there is fresh, healthy food to eat for meals, not processed, boxed or frozen meals, which, typically, have way more sugar, fat and sodium than we need.
You'll also need to make sure you keep your portion sizes in check... while chocolate can be good for you, you need to limit your consumption to only one serving/day; that's something that only you can do. If you can't resist the chocolate, you should ask your parents (or whoever buys the food) to stop buying chocolate... if you don't have ready access to it, you won't be able to eat it.
There may be other ways we can help you, but we need to know what type of help you need. Some information about your lifestyle would be helpful, as well, since the most lasting weight loss is actually lifestyle changes.