If air supplies get exhausted how will it affect our life style?

Our life won't work without air; we'd die. Fortunately, oxygen gets created by plants. The problem is that we're overpopulating the earth, and at the same time tearing down the rain forest (our biggest source of oxygen) for farming. The directive to "go forth and multiply" has long been obsolete, and religious zealots should stop their rampant over-breeding for the purpose of taking over through numbers.