A standard, static page is similar to creating a post, and is ideal for creating an About or Contact page for your website.
To create a new page, navigate to WP Dashboard > Pages > Add New.
Like a post, you can enter a page title & add content.
Additionally, you have the option of choosing between a number of page layouts via the drop-down menu on the right titled "Template":
Default Template (sidebar page layout)
Full Width Page layout.
Thin Width Page layout.
Once you've published your new page, it will not automatically appear in your main menu. For a tutorial on adding items to your main menu, please see: Set up navigation menu.