Our democracy was not designed to have a “king” at it head. Read the constitution, he is not empowered to create law or domesticate policy. George Washingtonian saw the position as an executive admin and commander and [in] chief.
You are correct. But Trump thinks he's the CEO of USA Inc., and can run the country as he wishes, without constraints. The US Constitution, and the balance of power among the 3 branches of government, are totally alien and unknown to him.
Trump simply doesn't have the capacity to understand his correct role as US President. Add to that his dangerous megalomania and this is what you get.