1. how is pressure related to force and surface area?

Air pressure pushes all around you, it is the force of air spread over the surface area of your skin

pressure is the measure of how much force over a certain area

this is an example
imagine putting a 10 pound weight (disk) on your stomach (not dropping, puttting), not too hard right, now imagine that it was 1 pin that was 10 pounds, that would hurt, the force is still 10 pounds down but the surface area is alot smaller, more pressure