With all the functionality offered through our pages and sections, it can be very confusing if you don't know what the difference is.
Generally, when creating a page, the page name appears in the navigation. Sections make up the contents of each page. This means you can create a page with just 1 section, or you can create a page with as many sections of content that you'd like.
To add sections, you will want to move the switch in the top left corner of your Greenhouse to Advanced Mode. This will allow the Edit Sections button to appear within the Site Editor. You can learn more about adding a section here.