A childhood belief about politics

I didn't realize the whole checks and balances thing when I was little, and I thought the president could just order something to be done, and it would have to be done. So I always wondered why he didn't order the nation to reelect him, so he could be president forever. I thought that maybe the ONLY thing a president couldn't do was order himself to be reelected, so I thought that he should confer with another country, and come to an agreement that if the other country's president would help his pass a law so he could be president forever, he would help that other president in doing the same thing. At least that's what I was planning on doing if I ever became president!!