This is the sound name. You will use it in every part of the plugin and also in Minecraft vanilla /playsound command.
"music.song_1":{
This is the list of sound files Minecraft will play when you call the sound name.
Minecraft will play one of these sounds randomly (only if you set more than one sound).
Keep in mind that you have to change my_sounds to your own namespace name if it's different!
"sounds":[
"my_sounds:music/song_1"
]
For example if you want to have random sounds for the same sound name you just have to create multiple .ogg files and put them like this: