Reduce the size of Youtube Video?

Hello all WP friends!
I am new on WordPress but i already love it jaja,)
I begin a website and i would like to put a Short Youtube Video first only on the Italian part for testing.

so after a lot of time i succeed with this code with 9-16 ratio and using WP Code plugin to insert by php:

$langue = get_locale();
if ($langue == 'it_IT') {
    $content = get_the_content();
    $has_video = preg_match('/<div class="wp-block-embed__wrapper">(.*?)<\/div>/s', $content, $matches);
    if (!$has_video) {
        echo '<figure class="wp-block-embed is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-9-16 wp-has-aspect-ratio"><div class="wp-block-embed__wrapper">[youtube https://www.youtube.com/watch?v=tU57SYRZclI]</div></figure>';
    }
}

I try to reduce the size of the video by 50% by many way but it didnot work good!

I guess there is a simple command to do but i don’t find it,)…

You can check here at the end of the page that the video is too big:
https://wikihhc.com/it/
( only on /it/ folder)

??</img>Thank you so much by advance,)??</img>

The page I need help with: [log in to see the link]