I just repaired my small rock ding in my boat. Bought a fiberglass repair kit from West Marine, and did it myself. Very easy to do yourself, if I can do this anyone can.
If your looking to repair the gelcoat you’ll need to get with someone who can provide you with a matching gelcoat. Gelcoat is still active after catalyzing so you need to use a patching agent which is basically a wax that will rise to the surface of the gelcoat and seal it in against the glass. You can then wet sand the repair and blend it back in. Actually there are a few ways to fix this. A patch kit on the back side of the damage with some bondo and marine grade paint on the front.