Family Property Dispute

My uncle has 2 sons (both married) and both sons living in house constructed by uncle (not ancestral house). However there are regular disputes in family and to avoid further dispute elder son want to get separation from his younger brother and parents. However, parents and younger brother are not willing to provide equal share to elder brother in property and family assets. In view of above, my query is as under:- 1) Whether younger son and father can deny right to the elder son on father's property? 2) What are rights of elder son in his father's property and assets earned during joint family (equal share or 1/3rd share)? 3) Whether father and younger brother can throw elder son out of house without giving any share? 4) what are different options available with elder son to protest himself against mis-appropriation of father's property and assets? 5) what is validity of understanding signed by all family members on plain paper (not in form of agreement / unregistered document) for distribution of property rights?