How to disown parents

I am 21 years old. I am pursuing graduation final year. And this time i am financially dependent on my parents. I was born in a small village in solan district of Himachal Pradesh. I was bred in my village upto 8th class. For further studies i leave my hometown. My relationship with my family is not too good according to me, as my parents supports my younger sibling. And my parents choose my studies according to them. I want to join indian civil service , but my parents are losly supporting me or not supporting me mentally . Everytime the are disturbing me mentally . They don't took proper stand for me anytime. They want me to live according to them which is impossible , as i am adult i have my tight to live my life as i want to live. I want to disown my parents from long time but i thought it will not good for my government job. But this time it's going out of my control . Disown my parents will help my younger brother to live happily , as he always want me to get out of the family.