There are two ways to enable page editor to edit page.
1) In Content -> Pages find the page that you wish to edit in the page list. Click "Edit" button to start editing.
2) Log in as admin and go to the page that you wish to edit. Click "Enable Page Editor" on the top left corner of the page.
Here are the descriptions for the fields in the Edit Page section.
The name of the page. We recommend use English string for this field because it's part of the URL for that page. The URL is <your site>/<page group path>/<Page Name>.aspx . If you want to display the page as the localized string, use Title (see below).
Select the page group for the page.
Set the integer for this field. When user clicks the Page Group URL the default page gets displayed. The default page is the page with the smallest Sort Order in the current page group.
Check this if you want the user to be registered user in order to view the content.
Page Title is SEO field. You can localized string for this.
Page Description is SEO field. You can localized string for this.
Page Keywords is SEO field. Use commas to seperate keywords.
Put any extra meta tags that you wish to display. E.g. <meta name="google-site-verification" content="blah" />