Inherited property from my great grandfather

Hello There, My name is Santhosh, there is a family property of ours, which is still under the name of my great grandfather. And the ownership till now is not changed on to either my father or his father. Now my father has married for the second time after my mother's death and he is not interested in giving the property to me and says that am not even his son. So would I be eligible to get this property directly to me if I file a case? I do not want the whole property, my father has 2 other brothers let them divide the property and give my share from it. Could you please advice the best way to get this? My family details are as given below My mother passed away while I was 8 years old and I have a younger sister from my mother's womb and 2 step sisters. After my mother's death my father has neither taken care of us and he doesn't want to give this family property as well. Now I am 31 years old and married and have kids too. Please render the best advice on how to take this forward legally. you can please contact me on my mail- [deleted] Thanks