Whether you are entitled to take any property depends on the order in which your relatives died and whether they had any estate planning documents that specified who should get
their property and how.
The rules that apply to dividing up property take effect when a person dies, and beneficiaries must be alive to be entitled to take property. So if your father died before his parents, their property passed to those in line to take it after him.
To find out who is entitled to get what in your family situation, pay closest attention to the person who died last, and what property he or she owned by law. If your grandparents both had wills, the determining document would be the one belonging to the last one to die. If that person died without a will, which is also called "intestate," the property will be divided according to a hierarchy set out in state law. To find out the specific law in your state, do a search of your state’s name plus "Intestate succession."