Can grandfather's will be challenged if name not included

My grand father had 3 son 1st as 2 son 1 daughter 2nd son not married 3rd son as 1son I'm son of 3rd I was born in 1991 In 1995 my father wo Ez the 3rd son my grand father died My mom was torchred there by 1st son and wife soo she left tham and married another man My grandfather had a site in Bangalore but my grandfather has made a will in which my name is not included in division on that site Thay have showed names of 1st son 2 sons name and 2nd son and my grandfather is dead already can I challenge the registred will which is made already As per to my knowledge thay have misguided my grandfather father stating that thay have included my name also to my grandfather but thay have excluded my name and put the 1st son 2 children's name Can I challenge the will or it's over on there name but I don't have any proof to prove that will was fraud because even my grandmother is dead the only proof I have is that I'm is grandson soo can u help me with it