This page is for information about your community. You can access and edit it by going to the Website Builder, click the pages tab at the top, and click 'edit' next to the About page.
Most organizations use this to describe their purpose, possibly contain contact information or list officers and members. If you have no such need for such a page you can go into the pages section of the builder and delete this page 'About' . Remember to then delete these pages from the main navigation and the footer navigation lists.
The rest of the pages in the navigation are modules within the website builder that pull content from the OrgSync backend. They require no maintenance or editing, the content is generated without any need to update it in another spot. This is not the full list of modules, you can include more if you so desire by accessing the builder, adding a new page, and then clicking the OS Modules button in the top left and choosing your desired modules from the dropdown.