Okay kiddo, imagine the ocean is like a giant backyard and everyone who lives near it wants to use it to play or search for things like treasure. But just like how you might have some rules in your backyard, there are rules for the ocean too, especially for the deep part that's called the seabed.
The International Seabed Authority is like the grown-up who helps make these rules and keeps everyone fair and happy. They live in Jamaica and make sure that people from all over the world can explore the ocean floor, but they do it in a way that doesn't hurt the environment or take away things that belong to others.
So just like how you and your friends might take turns playing with a new toy, the International Seabed Authority helps countries share the ocean resources fairly and take turns exploring it. They make sure everyone follows the rules and that the ocean stays clean and healthy for many more years to come.