If a population of 5 has only food for 3 2 will starve or die in some other way before they starve for equilibrium to be reached.
The same goes for 50 and 30, 500 and 300, 5000 and 3000 etc etc
Scale does not change the realities of nature.
The Earths volume imposes a scale and mankind's ingenuity can move some of the levers ( ie improved food production eg more carbon dioxide helps as does fertilizer ) but these things can increase pestilence, aggression, pollution etc that also apply.
As I said your IQ is rather limited.
Too many people is a problem - not carbon dioxide.
