I feel hopeless. Me now. please help!

I feel like I was made to grow up too fast. I didn't got to enjoy anything in life. I was forced to leave school and isolated myself because of poverty and egoistic parents who could've easily save guarded my future with help from my relatives. Although I recovered my character and personality with every resources I had. I never could complete schooling. Or had confidence in socialising. I have no friends. I try anything to fit in. I ended up offending everybody. While trying to do any job. Bad thoughts comes into my mind. Thinking this is how it's gonna be for the rest of the life. I am sane enough not to commit any self harm. I need some confidence, some happiness and not be sensitive. Like I get scared whenever anyone yells. Not even at me. Or make caustic remarks at me. I have ambition to complete my schooling and getting into a good university. I hope it's not late. Please suggest me medicine and diet to boost my serotonin. Nothing makes me now. Please help!