Does Trump even have a clue?

Trump says that his Supreme Court nominee would investigate Hillary Clinton, presumably in between signing bills (?)

Does the Donald have any idea what judges do? Does he have any notion whatsoever how our system of government works?

Could he pass a citizenship exam? Could he pass a grammar school civics exam? Does he have any idea what a Supreme Court justice actually does?

Does he have any idea what the President of the United States actually does?