If you're looking to create a tag yourself, versus hiring a developer, you should look at a more simple existing tag, like the old MySpace Video tag at UBBDev:
https://www.ubbdev.com/forums/ubbthreads.php/topics/316983/custom-tag-myspace.htmlYou'll see how it simply grabs the id out of the url, then where that variable is populated to the "resulting markup" and just replace all of that with how the embedded URL would look on your forums.
