How do you get the treasure chest by bannan island?

To get the treasure chest by Bannan Island, first, ensure you have the necessary tools or items, such as a boat or swimming gear, to reach the island. Look for clues or maps that might indicate the chest's location, often found in nearby caves or underwater. Interact with the environment, solving any puzzles or overcoming obstacles that might protect the treasure. Once you locate the chest, simply approach it to collect your reward.