Elder brother tricked father into transferring all the property in his own name

Hi, We are four brothers, of which two of them are settled and have their own properties in Nepal. My elder brother tricked my father into passing all the parental (rural) property in his own name - he forcibly tricked my father to the district court offices and got his thumb impression on forged property papers. The property was originally decided by my father to be divided in two half between my father and myself. My brother was a Forest officer with the Govt of Bhutan and had moved to the town at a very young age leaving behind NO INTEREST AT ALL in the village property. It's a 15 Bigha land, 7.5 each for my father and me. I have been asking him to undo this and give me my share of the land but he is in denial and says that we will only give 2.5 Bigha and keep/sell the rest. He already has a very huge REGISTERED property provided by my father in the town. Although I have a small property in the same town too, it is unregistered land. I spent my 40 years in the village property, taking care of it along with my father, planting trees, betel nut farm, etc. and that is why my father had planned to provide me 7.5 Bigha of this land of which I am a rightful owner. It has been about 4 years of following up with him but now it looks like that he wants to keep everything for himself. What should I do? Whom can I approach? My father says he has given it to my brother and he will settle it, I have nothing to do anymore. Is there any legal action that I can take against my brother? I am a family person and do not like to take my own brother to the court, but he seems to be getting selfish and greedy. Please suggest a detailed plan of action to get my rightful property back. I and my wife have been under stress for several years because of this - I have two sons (32, 29) and a married daughter (26). We live in the Alipurduar District, West Bengal. There are not many good lawyers here and most ask for a hefty sum just to initiate a conversation. Please help. Thank you in advance.