I'm a Christian my family is bad though?

I'm now a 15 year old male, we are homeschooled, and my mom works and dad "does" our school. I NEVER GET ANY MONEY FROM ANYWHERE. My parents won't give me money, won't let me get a job, won't let me help for money, and will not let me accept ANY money from relatives. My grandmother sent me 100$ dollars onetime through mail and they took and told me they did and I don't need money. We never buy healthy food and my mom never makes anything for us. They get ANGRY YELLING about EVERYTHING. I got in trouble this morning because I didn't tell my dad good morning. My sister is a typical bratty teen that is younger than I am but my parents like her better. We call ourselves a Chrostian family but we are far from it. They don't let me buy anything, and every time I ask them if they can get me coffe or tea when they go out to a restaurant they tell buy it yourself: I CANT YOU WONT LET ME GET A JOB! My school is hard and my dad flat out just doesn't care about our education. He just goofs off all day and shops and plays his iPad and I'm stuck doing 10 grade hard Christian homeschool program alone. Whenever we go to church we rush out as quickly as possible so I can't make or have any friends and they don't let me go out with any of them. My dad and mom only care about themselves and each other. Is it a sin to just try to avoid them and abuse the fact they'll pay for my college and just hang on till then? I've only scratched the surface of how terrible this family is. Thanks for the help

Read more: I'm a Christian my family is bad though?