We’re carbon based life forms.
To deny that is to deny our existence.
“... to deny our existence.”
You are so correct.
The trees (which GOD created first), need CO2, exhale oxygen.
The humans (which GOD created 2nd), need oxygen, and exhale CO2.
GOD should get the applause for creating such a wonderful system whereby His creation (you and me) can have all the oxygen we need to survive.