What does it call when I write a paper to protect someone?

There is no such thing.

Your roommate does NOT become responsible for your funeral, or any of your debt. Even if your living together, in the same bed room, he wouldn't be responsible. The only way he would become responsible is if you got married.

If you have more then $100, then you should have a will. I'm guessing that your life situation is that your young and have nothing of great value. So you could just write a simple will.

I, Jim Smith, leave all my personal belongs to my parents.

Something like that. Later in life, when you have more, you can go to a lawyer and write a full will. If you have anything of value, if you have a child, then you should have a lawyer draw up a will. It only cost me $350 for a lawyer to do my will. That was a few years ago, so it might cost a little more.

You can just write a letter and have it notarized and a witness sign it next to your signature. You could also just have a lawyer draw up a document as well.

there is no reason for you to put anything in writing because no one except family is required to do anything.