How to distribute one single plot into two brothers?

Hi sir we live in Rajiv Nagar, Rohini Delhi area In 450 sq ft house. Me, my mother and my elder married brother with his 3 childrens. My father was passed away in 2017, he was also the owner of this plot, but he didn't make any distribution of property between me, mother and brother or my four married sisters. Me and my mother live in ground floor, and my elder brother with his family live on second floor, actualy the second floor is half built. so my big brother might be plannig to build the entire second floor. My question is, can this house be distributed in followings manners 1. After my mother died, I become the legal owner of ground floor, and my brother become the legal owner of the second floor? 2. Do my mother has a right to make a will such as: After i died, ground floor and third floor will be my small sons and second floor and 4th floor will my elder sons, also notice like i said third floor and 4th yet to be build, its the future thing. I want a kind of solution so that after my mother died, there would be no conflicts between me and my elder brother even if we live in the same house. Please also let me know what kind of claim my four married sisters can do in this situation?