I'm going to snap back at my parents.
That feels rude. Why do you need to snap at them?
I'm sick and tired of the way they treat me. They're always telling me what to do.
I understand that you feel frustrated by not being understood by your parents, and that's normal. But you should remember that they love you and they are providing for you, and maybe the better way to resolve the situation is act mature and talk calmly with them.
They treat me like I'm some small kid. I'm not going to listen to them.
I wouldn't recommend not listening to your parents. They have been kids once and they would know what you're dealing with better than how you're understanding it yourself, so I do suggest you keep on listening to them. And as I have said, I do think it is best to talk with them calmly in possibly giving you more freedom and telling you less on how to do things in your life.