Springs don't just break. One or both door check rollers are frozen and will saw a groove in the spring until it breaks.
It can be done on the car, but not easily. Look at the picture to see which direction the springs goes. It take small hands and 2 pry bars that are at least 3 ft. The straight end of the spring needs to feed up from the bottom. The end with the notch needs to have tension put non it with one of the pry bars. (It is a torsion spring.) while holding the holding tension on the spring, you will need the other pry bar or a long slotted screwdriver, (use a hammer) tap the spring down, behind the tang on the body side hinge half. If you do it correctly, there should be tension on the hinge now and the door will stay open. This is just a band-aide. The hinbge needs to be rebuilt.
Good luck. Print the picture for reference. Take it to the car and it will come to you.
Leo