Well his signature is on the Executive Order, and the order starts with “By the authority vested in me as President by the Constitution and the laws of the United States of America, and in order to promote the interests of American workers, businesses, and consumers, it is hereby ordered as follows:”. So I would say “hilariously wrong” and “poor understanding of civics” is a pretty bad characterization.

https://www.whitehouse.gov/briefing-room/presidential-action...

https://www.whitehouse.gov/briefing-room/statements-releases...