#1 - Go to your listings section
Go to your listings via "Listings" tab at the top of the page in your backend access to your new website, then click the "Listings".
#2 - Go to the Attachments Section
On the left bottom side Click the yellow tag "Attachments"
#3 - Paste & Link
Go to the "Youtube Video" tab. Now you can copy-paste your link in the box, and click on the blue button "Link Youtube Video" when you're finished !
#4 - Verify!
Verify the video preview frame is below the field! If not, check the URL first. If the URL is valid, make sure the Youtube video settings are set to allow embedding on 3rd party frames.