maybe a music player?

shiny exe how do i do that

you could try out webamp (there's a guide for it here: https://github.com/captbaritone/webamp)

This is good but I do not know what I would put here

do you mean how to add music? if you want to add audio files, you can use a file host (like catbox.moe) or find some on another website (like archive.org). (here's the code i use, feel free to copy some of it if it helps: https://shinyexe.neocities.org/webamp.js)