Legal remedies against sale of property given to son by father orally

We are 4 children mother is widow my father died without doing any will I'm the elder brother we have full site that's my father property I built 1 bhk home in 1st floor in my own money ground floor and 2nd floor belongs to my father's own money now my younger brother and sister are decided to sell the property but I don't want to sell the property my father only gave that place to build 1bhk home(i built my home with my own money) but he didn't done any will I want to save that property plzz tell me how to save my property I don't want to sell the property which case I want to put in court to save my property