A site can have multiple subpages which can then be added with different types of section (grid, PDF embed, image slideshow, video playlist and text).
When needed by your design, you can easily delete a subpage! Be careful though, as you might not be able to restore it back to your site .
To delete a subpage:
From the site editor's left sidebar, click the "Edit" button next to subpage.
Hit the red "Delete Subpage" button.
Confirm this command by clicking the "Delete Subpage" button in the pop up dialog box.
Note: A subpage cannot be deleted if it's the only subpage for the site.