I don't know how to buy a parachute.

log in, (obviously), click the "play" button. this takes you to the era selection. just click "play" again. this will take you to the plane selection/upgrade section. now click the image of the pilot with goggles on. this will take you to where you can upgrade your pilot. click on the parachute and if you have the $$ you can buy it.

this is how upgrades are purchased for planes, tanks, and your pilot. also where new planes and tanks can be bought.