Often you will want to embed content into your website from out outside source like Youtube. If you have worked with websites before you may be familiar with copying and pasting html iframe code into your pages. CNS Sites works differently and instead you will use the 'Add media ' button to insert content.
To embed media from an outside source you can click on the 'Add Media' icon from the toolbar. Then click on 'Web' and enter the url of the media you want to enter. You do not need to enter any embedding code, just the url of the content.