Once a year the air ‘buffer’ that keeps pressure in the water system needs to be recharged so that the pump doesn’t go on every time you get a glass of water. The air buffer tank should be 50/50 water/air. To do this:
Take the round cement cover off the well box and climb down in it.
Turn off the power at the big grey switch in there.
Open the spigot to the hose and let the water drain out until only air comes out. Shut the spigot.
With some kind of compressor (there is a 12v on in the closet now) attach to the hose to the nipple that leads into the air tank.
Fill with 15-20 ppsi of air. Detach compressor.
Turn on power.
Note that you did it in a comment below.