My father is a retried government servant. He was retried on medical grounds, and a certificate is also issued?

My father is a retried government servant. He was retried on medical grounds, and a certificate is also issued that the person should be is unfit to work on medical grounds, an was granted invalid pension. the question is do my father can take the senior citizen facilities for tax purpose, travelling prupose etc, due to the same reason, if it is so can you please send me the circulation copies of the same.

can a grandson had any right over the grandfather property or same the person over his father property?

can the property be taken form my grand father because he is in undue influence of remaining son (i.e of my uncle). further my father is no more able to work due to some medical grounds and the same my grandfather is neglecting to provide or divide the same and give the share of rights to my father. so is there any help over this matter. and further my grandfather had received the property from his father.