This is wrong as well. The only requirement to be US President is that you are over the age of 35, a resident of the United States for over 14 years, and be a natural-born citizen. Everything else is your personalized whiney rant of the day about what you think a president should do or how they should conduct their business interests.
You know what, you're right.
If a president wants to lie repeatedly, use his position of power to further enrich himself and his mates, make decisions which push the country in to the brink of recession, take no responsibility for anything and blame everyone but himself for his failings and just generally act like a complete asshat on the world stage and make himself and by association your country a complete laughing stock then you're right, there's no requirements to stop him doing any of that.
And yes, because of the MAGA Cult he gets away with it.
Where we differ is I don't actually think it's a good thing. I'd rather have a world leader with honestly, integrity and competence.
I'm a bit of an old traditionalist when it comes to stuff like that.