Plumbing help please

[randr]

2. Your system has a pressure air tank with a bladder inside

The bladder may have failed or the air chamber is empty. This situation usually causes the pump to come on over and over. Some newer pressure tanks have a nozzle to fill the air chamber to a desired pressure.
You also may have an air bleeding valve somewhere on the line. This is the likely culprit. It allows accumulated air in the system to bleed out without losing water. It is a small round metal thing with a cap that looks like a bike tire cap. Sometimes this cap is too tight and if loosened air will start to escape. If needed try to take the cap off and press the relief valve as if you were taking air out of a tire. If air does escape when you do this the valve itself should be replaced.