You need therapist. Several exercises can help with this. They need to be directly taught to you. I suggest you see a physcal therapist.
See a therapist. You need rotator cuff exercises and scapular stabilizing exercises but first you need a period of immobilization.
Difficult to say. It really depends on what direction the shoulder dislocated, the cause as well as the injury to associated structures including the muscles, ligaments, nerves and bones. The best person to advise you is the orthopedist who treated you for the dislocation.