What Are the Limits to Presidential Power, if They Exist at All?

Obviously, there are limits to presidential power as set forth in the U.S. Constitution, which Trump is exceeding almost every day. But can he rename the U.S. Capitol the “Donald J. Trump Capitol Building?”
He holds himself on par with Washington and Lincoln. Can he put his name on their monuments?

If the US Military Leadership would honor the Oath of Alegiance each one of them swore to when they received their Commission – this would end within 24 hours; because of two things in that Oath
1.) it was not sworn to any President or Govenrment
2.) it was sworn to the US Constitution – only.
And in the middle of that oath are the words — that they “will fight all enemies, foreign and domestic..
which they have decided not to be selective, i.e., only foriegn enemeies…..
You want your fixit – get the Military Brass to do their damned job and protect the Constitution like they swore to.