A hole in the fiberglass tub can be fixed. You just need to fill it in with a fiberglass repair kit. The kit comes with some fiberglass and a resin. Just mix the two together and apply the mixture to the hole. You’ll want to file the edges of the hole down after you apply the fiberglass resin.
If your fiberglass tub has a leak, it’s important to fix it quickly to prevent the leak from spreading. You can fix a leak by replacing the fiberglass tub liner. You can also patch the hole with fiberglass cloth and resin.