[nokcha]

>The president is not a CEO

The president is, literally, the chief executive officer of the US government. He holds an office under the United States, and that office is executive in nature, and it is not subordinate to any other office.

[boapnuaput]

You obviously are not familiar with the USA's Constitution. Please re-read it. In particular, Article Two, Section Four; "The President, Vice President and all civil Officers of the United States, shall be removed from Office on Impeachment for, and Conviction of, Treason, Bribery, or other high Crimes and Misdemeanors." This means that the President may be removed from office in certain circumstances.

In the time when the Constitution was framed, and in many times since, there is the meme of "checks and balances". [0] The overall idea is that no one branch of the Federal powers may be unilaterally or universally unabridged in its ability to act; other branches have powers which may check, veto, review, or otherwise neutralize certain actions.

So, why is the President sometimes called "chief"? Because, as Article Two also states, they are the "Commander in Chief" of the armed forces. When it comes to military decisions, yes, there is no office above the President's; however, note that the President's military powers are neither unilateral nor unlimited. Crucially, the President isn't able to declare war or allocate funds for military use without Congress' approval.

Hope this was informative. The USA's Constitution is a fascinating document worth reading, even for those not from the USA.

[0] https://en.wikipedia.org/wiki/Separation_of_powers#Checks_an...