Make sure you know what you are going to write about. Then prepare three main points for your argument (one for each body paragraph) and set out the most important things that goes with them. To prepare a thesis, take the question you're trying to answer and turn it into the answer itself like such: Question: Why do Timelords have two hearts? Answer: Timelords have two hearts because (and then put the point you're trying to prove) because they are aliens. Then comes your statement of enumeration (which isn't always taught but is still important). After your thesis, construct a sentence that has your three main points in it (list them in order of your body paragraphs, I suggest from least important/relevant to most). It would look like this: Timelords are aliens because [u]they are far more advanced than we are, protect the universe, and come from a different planet than us.[/u] Set up your introduction to let that be a part of it. After that comes your body paragraphs, and lastly your conclusion which should sum up everything.

wow your good

What is preventing you from writing the essay? Once you explain this to me I might be able to help.

I don't really know but everytime I tell myself i'm going to do it and about to start I feel lazy not wanting to type at home but in school i can :/

Since it seems to be bugging you that you can't just sit down and do it, use that as a reason to do it. Instead of worrying about it, you could be doing it wrong now and getting rid of that feeling in your mind. The first step is the hardest, but once you start typing you should be able to keep going for a good chunk of time.