Regarding Property

If the property is self acquired by your father . then he has the right to sell and transfer to anyone. after the demise /death only u can claim for the same. if the property belongs to grandfather then u can claim for the property now also when your parents r alive.

legal heirs can claim fr d property after death of real owner otherwise they can not

no only if u will Claim partition

yes

if real owner are alive so there after his children

legal heirs