About power

Hi, am from kerala. Am a hindu. I want to know about my mothers property. My mother was died before 2 years. And my father marry another lady after 1 year of my mothers death. That property is in my mothers name. That is the property which was the share of my mother ( from mothers father). And my father was didn't care about me and my mother. He didn't take any care of us. Before my mothers death. And also my father is misbehaved to me so many times and speak ugly worlds that which men can't talk to our daughter. And now am living in my job place. I can't live with them for this reason. And now I lost my job, searching for a new job. The problem is my father and his second wife going to sell that property which is still named my mother. And also original property document is with me. And how can they sell that property?? And I want to stop selling? I heard about that they make agreement and take advance from buyers. This all they do without my permission. And how can I stop this? And did they have any power to sell that without my permission?