Pages vs. Posts
Largo follows the WordPress way of creating content, which consists of two basic things:
- Posts - which like a regular blog post appear in reverse chronological order on your homepage
- Pages -which live outside the blog chronology
Posts are for news stories, commentaries, and other time-based articles. Pages are for timeless content like your "About" or "Contact Us" pages.
Pages can be organized
http://yoursite.org/about
http://yoursite.org/about/staff-list
You could then add About to the main navigation menu as the parent and the child pages as drop-down menu items under it.
Beyond the above differences between Pages and Posts, creating and editing Pages is very much like it is for Posts. To create a new Page, click on Pages > Add New or the New link at the top of the dashboard and select Page.
Like Posts, Pages have a Title and a Body Text field. You can add media and Featured Media in the same way as Posts, and save a Page as a Draft as needed. By default Categories and Tags are not enabled for Pages.
Page Templates and Sidebars
In Largo, the default template for Pages uses a single column layout. If you need a wider page layout for embedded interactives, maps, etc., you can select the Full-Width Page template to display the content in a wider single column. (See the Embedding Interactives page for more on this.)
You can also use the Two Column (Classic) template and select a custom sidebar in the Page's Layout Options panel:
Site administrators can create custom sidebars with appropriate content for a given page, or set of pages, then you can use them as needed.
More on Pages at the WordPress Codex
Everything you ever wanted to know about Pages is available here on WordPress.org.