Can I claim property given by grandfather years back

Hello Sir, We the people belong to nawab families. My name is ismail sheriff ,Age 63. my grandfather (nana) who hold 500 acres of land at the time of british govt. The british govt had made the deal with my grandfather that to hand over the 500 acres of land to the govt ,instead of that the govt will provide the pension for 7 decades. After the death of my grand father my mother zaheera bee had started to receive the pension till 1990's .After my mother expired ,I went to gulf for some years and came back in 2007. now i am here to claim that 500 acres of land which had been taken by the govt instead of that 500 acres i am here to claim atleast 30 acres of land and a home in amir mahal and The prince who is leaving in amir mahal he is coming from 38th decent and we the family of nawab people are coming from 33rd decent .So kindly suggest me how to file the case.