Display Youtube Link in WP Post

gistfile1.txt

/*Display Youtube Link*/
add_filter('the_content', 'add_my_content');

function add_my_content($content) {
    $my_custom_text = get_post_meta(get_the_ID(), 'youtube_link', $single = true);
    $embed_code = wp_oembed_get($my_custom_text, array('width'=>720, 'height'=>420));
    
    if ($my_custom_text) {
        $content .= $embed_code;
        $content .= '<p></p>';
    }
    return $content;
}