The Sites page displays all SharePoint site collections in the tenant (excluding individual OneDrive sites), and shows what type of sharing is allowed (that is, no external sharing, new and existing external users, or anonymous guest links allowed). You can edit the type of sharing here.
If you choose Add a site, you jump to the SharePoint management portal, to the page for creating a new site collection. That's outside the scope of this chapter, but is covered in Chapter 6, Administering SharePoint Online.
