Add video from youtube in post

This is overview how you can make it working:

First with below code you can detect youtube URL for details Please read:

$reg = preg_match('|^\s*(https?://[^\s"]+)\s*$|im', $post_id_63->post_content, $matches);

 if (!$reg) return false;

 $url =  trim($matches[0]); // youtube video url 

 echo wp_oembed_get($url); // this will return youtube vidoe 

For details please read: Wp_oembed_get

we need to use wp_oembed_get to make URL into video from post content

Thanks!