How is air filtered with in the human body?

Air enters through your nose or mouth to your air sacs.

Well for starters the air comes in through your mouth. That allows oxygen into the lungs which in turn pumps oxygen into the veins.

Try asking the question before drinking massive quantities of alcohol.

imbalanced pressure can cause nose bleedin and also if you tavel about and thru many and different areas of pressure your ear kinda blocks but u can "fix" it by yawning