How can i get the property of my father in brother name

My father is having property but he is expired in our school days. My brother had been taking care of us since my father expired. Almost after 20 years of my fathers death my brother planned to register a plot(land of 200 sq yards which is now at the cost of 50000 per sq yard) which was on my father name to his name. For which he needed the sign of entire family along with me. Since i dint agree to that he made promises that he will give something to me later and forced me to sign at that moment. But now after the registration he is simply ignoring me and all promises. I want to book a case on the property and get my share now.Can you please suggest me how can i proceed? Other that the plot i mentioned above there is one more constructed house in which my mother and brothers family is staying. And there is about 6 acres of land in our village. All this property was belonged to my father, but i am not sure if my mother or brother did any registration of all this property on to there name in anyway.