I live in the state of Florida. A couple of months ago, something told me to go see my father, only to discover by his wife that he had passed. I was never contacted and or told of his condition. Do I have any rights as his only living heir? (aside from his current wife) which is not my mother.

Did he have a will? If not, then his wife is an heir and gets 50% of the estate. If you are the only other surviving descendant, then you get the rest.

If there was a will, you need to see if the will or the estate was submitted to probate. From there you you can see if you are entitled to a portion.

If the estate has not been submitted to probate, then you may have to go to court to force probate.

Did you step mother give any reason why you were not contacted? When was the last time you spoke to your father?