Setting the Scene
Scratch has a library of backgrounds and sprites for you to use to make your project look awesome.
Select the Stage.
Click on Backdrops.
Click the Choose backdrop from library icon.
Then pick your favourite underwater background!
Great! Of course, now you have a cat underwater, and cats aren’t usually big fans of that. But you can fix that, because you can turn the cat into a shark!
First, select the cat sprite and click on the Costumes tab.
Then, click on Choose costume from Library
Select this shark image and click OK.
Now remove the cat costumes by selecting each of them and clicking on the x.
Now you have a shark – excellent!