You can actually leave that section blank. For example here's a code for autoplaying music:
</style>
<iframe width="0" height="0" src="https://www.youtube.com/embed/#######//?&;amp;;autoplay=1&;loop=infinite&;controls=1" title="YouTube video player" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen="" loading="lazy">
</iframe>
The only thing you'd need to do here is to copy and paste the series of numbers and letters after the = in any youtube link into the section where the hashtags are.
Common mistake: not ending the style before putting in the code! This is why I usually leave this code to last.