Layers - is a tab where you can see all components from selected section.
Under this tab you are able to edit your components, duplicate and delete them.
Learn more about How to move components?
Pages - is a tab with different web pages.
Web pages each have a URL or address, which is how a page is found, and is different for every page.
Here you can add pages, edit and delete them.
Learn more about How to add pages? and How to delete and manage pages?