Can I reuse the Armature and action like example a man and I want to reuse the armature and action on another mesh like a girl. Can it be doing? Do I have to redo the enveloping on my girl than?
yes and yes and yes. You can file-append the armature and all its poses. However, the meshes are different, so you have to parent the armature to the girl mesh, let Blender do the auto-closest vertex to bone assignment thing, and take it from there.