The legal side first - At 16, you're still classed a child, and the responsibility of yourself falls to your parents. Legally, they have to provide you with the basics under parental responsibility (Set out in the Children Act). This includes a safe home and environment, education etc, and then to have respect for your belongings.
Are you able to comment here on the reasons why you want to leave? Are you safe? As its an incredibly sad thing for a young person to want, as it appears you have no real options of a loving home from your post.
Financially, at 16 you are not able of applying for benefits and housing. I would go into your nearest children's centre and explain the situation to them. They can assess your safety and the problems and try and come up with a plan. They cater for 0-19s. If you are still at school, you can speak to your school pastoral team, but sometimes they aren't the best at taking young people seriously.
I really hope you are ok.