Before you deal with exterior cosmetics, I’d want make sure the floor and frame are solid.
Do a very thorough inspection of the floor from outside and inside, paying special attention inside benches and lower cabinets around the outer perimeter. Look, poke gently with a screwdriver, and smell for signs of water damage.
Check the frame for cracks, repairs, or deep rust. The likely trouble spots are under the front of the cabin.
Returning to the shell, gelcoat repair is possible but expensive if the area is very large. Paint- typically a marine topside product-is an option.