The answer to this question is very simple - keep completing the tasks in the right part of the screen and follow the hints.
During the tutorial, you can do only those actions the game asks you to do. It’s made with the intention to show the basic principles of the game, how it works, and what you can do there. This information will show you how to progress further.
The tutorial lasts not that long, on level three you will already have the opportunity to move more freely on the island, and by level five you will be completely on your own, ready for the big adventures. You will be free to explore before you know it.