How to stop my father from selling ancestral property. I am 30 year old and my elder brother is 32.?

My father is two brother. My father is the elder one. I am two brother. My father and my uncle got their share on Panchnama which has been notorized. My father has been selling his share without involving me or my elder brother. How can I stop him from doing this. And what are proccess of getting my share. What would be the time duration taken by the court to If I file Tittle suite.