If for any reason, you need to delete a store, go into the store builder and navigate to the page manager on the left-hand side, click on store settings the top, and scroll down to the bottom here. You’ll see the option to delete your store. Deleting a store means it has gone forever and you cannot recover a deleted store.
So if you would like take screenshots of your store before you delete it. So you at least have a digital archive for the content that you have created.