Without energy we can't do work cuz we can't apply ne force on an object. Gravity, itself a force, when, say, pulls a ball down to the gorund it actually does work. Now for that force, where does it get the energy from or what type of energy does it have?
If u have a book opened n u hold a page up frm it n then leave it so that it slides down to it's original poisition, has work been done by the gravity?
The work gravity does is increasing the kinetic energy of the falling object, dissipating that kinetic energy into heating and moving air (air friction).
I am not certain what your second question is, it is far from standard English. When one separates two objects, one does work against gravity, when the objects come closer, gravity does work.