you could try out webamp (there's a guide for it here: https://github.com/captbaritone/webamp)
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)
deviantart and tumblr are pretty good resources for finding free to use blinkies and graphics ^_^
I'm at school these don't become options until later
oh well this site ( https://rentry.org/resources ) has some links to blinkie pages, hopefully they can work for you!