1. You're on a computer, so therefore your parents care enough about you to buy you something that is NOT a necessity.
2. You have a roof over your head. I know parents that don't provide that and the children end up in foster homes due to Child Protective Services.
If your parents did not care about you, they wouldn't spend the time and effort to give you a house, clothes, AND ESPECIALLY A COMPUTER.
The irony in my post is I've gone through so much worse than you and I am so thankful I am almost 18. What YOU need to do is own up to some sort of responsibility and stick it out until you become of legal age to live on your own.
If you run away I guarantee the cops will find you and that you'll be sent back home or possibly even worse, sent to a mental hospital or the government. GUARANTEED.
Wait until you are 18/legal age. Then you can leave LEGALLY and SAFELY.