My father is not ready to give me my part of land

Dear sir/madam, I am 35 years old man from Bangalore. I am married. My father is married two times and my mother is the elder one. With out divorcing my mother or without taking permission from her he married again when i was 2 years old by sending my mother to her native. But after 2 to 3 years When i was in 1st standard he came to my mother's native and took back me and my mother to his house again. After that we were in the same home, in the mean time my father has been beating my mother often times and in the mean time my own sister has born. So after completing my 10th, me, my mother and my sister moved to bangalore because i dont wanted my mother to suffer more. 15 to 18 years passed. Now when i tried to contact my father and told him that i want my part of land which belongs to me, my mother & my si ster. He is telling that he wont give anything to me as he has borrowed money from other, and if i want the property i have to give him money he borrowed from others. That was my grand father's land (father of my father), it has been transferred to my father's name before my grandpa's death. So how will i fight legally with this situation and take back what belongs to me, my mother and my sister. Please help me. Thanks in advance.