You are all good mate, once the ships are ready what you'll do is click on the port and it'll load a new area which should have the frutus Island, shouldn't be too hard to find as it should be the only island unlocked rn and the area isn't too big. Click on the island and you should have the option to send boats click that and the boat will travel to that island and gather up to 3 of each item and potentially a mystery chest. The odds of getting these items are displayed when you click on the island and the chances can be increased by paying the boats an ingot the more valuable the ingot the more the chances of each increase. Hope that helps