Need help making a sound resourcepack

Hello it's me again. This time I need help on how to change the c418 music discs to custom music. I don't want to add a custom folder, I want to specifically change a default record to a custom song. I already have a resourcepack with textures that works, but no sounds in it. So also how do I add the sounds folder? You guys have been way more helpful than anyone on youtube or reddit, so I'm coming here first