How to deal with Domestic Violence?

I am a final year BTech student and currently interning at Bengaluru. I am of a Telugu family from Hyderabad. I am speaking on behalf of my mother also. We are facing domestic violence for the past almost 22 years from my father and his sister and are a middle class family. We had faced instances for example, like turning off the power in the flat, pouring water in the flat, taking my school bag away during my school days, on pressure made my mother sign on some bank documents by blackmailing not to give my school bag. We would like to break ties with him completely now as he has created a scene at my office also and is threatening me now that he'll badmouth me at my school, college and office; put false parent harassment case on me and false cases on both of us and has become unbearable. I would like to know on how we can proceed legally and know more about the process.