primering my car

im new to the boards, but i have some questions about primering my car. ive painted the interior or my car but i avent done any work on the exterior. currently the paint job on my car is pretty bad and it needs some work, but i dont want to paint my car just yet. i want to primer the entire exterior of the car but not add paint for a while, how do i go about doing this and can i leave my car primered without a clearcoat or something. any tips or help is appreciated