Welcome Ramadulla
Your parents sound quite scary so I'm not sure if reasoning with them, telling them that you don't have to pray because there is no compulsion in religion, is the best advice to give. If you truly think it is, then go ahead but I'm 99% sure that you yourself will know that is a bad idea. I say I'm 99% sure because I have been in a situation similar to you. The only difference being very ironic indeed, and thinking about it sometimes makes me laugh, sometimes makes me cry. I converted to Islam when I was just a year younger than you and I went through hell to uphold my religion. I lived with my mother who was Roman Catholic and she didn't like Muslims or Asians much at all. My brother converted to Islam before me and my mother went crazy at him. She wouldn't speak to him for ages and when she finally did, she would still make malicious references to it when he was around. My brother's wife had a problem with her, at one point losing her temper saying she didn't want to be in the company of a racist. My mother left him out of her will and made a formal reason that stated she didn't want to leave him anything because he converted to Islam and changed his name. I knew she wouldn't take it kindly if I told her I was a Muslim.
Whenever I asked Imaams and Muftisaabs what I should do they told me to be good to my mother but don't tell her that I was a Muslim. I'm not sure what the reason was but to be honest I'm glad I never told her, otherwise she would have died knowing I was Muslim and probably thinking her line in the family was going to become Muslim, since her only other offspring was my sister who has never had a kid and probably never will do. On the other hand, she definitely had her suspicions that I was Muslim. She made me eat ham whilst I was a Muslim at dinner once and I was crying my eyes out in front of her. She didn't ask why I was crying. It was a dead giveaway when I look back on it. Parents know their kids very well and that is something you should always remember. I always thought the advice my Imaams and Muftisaabs gave that I should "keep quiet and just bear it for now" was rubbish advice, but now I find myself in the same position giving the same advice to you.
Although listening to your situation makes me feel very sad, I do think there is one advantage to being a non-Muslim in a strict Muslim family than being a non-Muslim in a strict Muslim family, and that is that there is nothing significant which a Muslim family requires of their non-Muslim child which their non-Muslim child is not allowed to do by their own conscience. For example, unless you have converted to another religion, it wouldn't be against your conscience to go into a mosque and pray. It might be against your conscience in the sense that you feel you are being hypocritical or deceitful, but the Muslim in the non-Muslim family bears the same shame. Eating halaal meat is not against the non-Muslim's conscience either.
Can I ask, has your father threatened to kill you because he fears you might leave Islam? My mother threatened to kill me on occasion but not because she thought I was going to become a Muslim, but just to scare me, as I don't think she would have really done it. Do you feel your father might be the same?
Either way, back to my point that your parents know you very well, better than you think. My mother asked me if I was a Muslim once. I was absolutely flabbergasted! I wasn't expecting that question to slap me in the face there and then. I lied to her. I knew I had to. But what amazed me was how calmly she asked the question, as if she wasn't going to do anything if I said yes. I have to admit, it was tempting to just tell her, since she seemed so calm. But deep down I knew she'd most probably have literally kicked me out of the house with her rubber boots, onto the street, shouting at me never to come back again, without concern for what her neighbours might think. If they ask you if your going to leave Islam, I suggest you tell them, no, unless your convinced they're not going to mind.
It's very comforting to know that you have a social worker to support you. It's quite surprising to me that a social worker recommended this site... Is this site really that recognized?!?! I havn't been around long enough to find out, so it seems lol. I wonder if the administrators are surprised at all?
Wanna share your thoughts on Islam with us?