I want to put a YouTube music on my site, in AutoPlay and background, could you send me the codes?
A simple google search on how to do this with code provided:
For local file: https://www.w3schools.com/tags/att_audio_autoplay.asp
Youtube, set width and height to 0;
<iframe width="0" height="0" wmode="transparent" src="//www.youtube.com/embed/VIDEO_ID?autoplay=1&loop=1&playlist=VIDEO_ID" frameborder="0" allowfullscreen>