Who gets share in grandfather's property if we have step brothers

Sir, my father & live his brother live together. My father give to some cash to his brother and say that i am busy so you go uit and purchase the house from uit. they went to uit but purchase the house own name. My father think he is brother so take in future, A long time, approx 45 hrs, my father ask him to give the house (5 Plot). they refuse and say that it is their property and not give one inch land to my father. They report in police choki , we also report the police choki but now they go to SP and SP said to police choki that he arrest us and give the paper of land now what i do ?