If you can’t lift your garage door you may have a broken spring similar to the one shown in the photo. If a spring is broken you can see the separation. Most double car garage doors have two torsion springs but only one may be broken and it can keep the door from opening.
CAUTION! Replacing garage door torsion springs is very dangerous because the springs are under extreme tension. Broken torsion springs on overhead garage doors should be replaced ONLY BY AN EXPERIENCED TECHNICIAN.