Even if just asking in a post already made it is good to post your store's link so people can see what is happening.

Did you make sure all the files are uploaded and in their proper places? In her folder to upload many are listed in the main area of the core files ( like includes/languages/english/html_includes/define_about_us.php)

Many files are "safer" like when upgrading if you put them into their override folder in the folder...in this case html_includes/your-template-folder-name/then the file

If it does not show in the admin define page editor then you will need to edit the actual file in the html_includes folder.