Ancestral Land

My great grandfather and great grandmother have died without a will. They had two sons elder one had 4 children and my grandfather which was the younger son has 5 children. My grandfather's elder brother has also died without sharing the land with my grandfather. We have ancestral land in Himachal which is still undivided. My father wants to build a house but we are not sure how to proceed legally in order to get a clean share of land where no one else can ask for their share in the future. We are willing to provide all others their part of the land but we want to assure the land where we are building the house will not become disputed since it's not in my father's name yet. Can you please help with how we can proceed with the legalities to get that share of land in our name? Thank you in advance.