How do I delete my entire music Library and start over?

Hey MiamiMateo,

If you’re using Apple Music and you have Sync Library enabled, yes. Take a look at this article for more info:

Turn on Sync Library with Apple Music

If you don’t use Apple Music and you used your computer to manually sync the music to your iPhone, follow the steps here to turn off syncing and remove the songs.

Kind regards.

Hey there MiamiMateo,

Thanks for reaching out to Apple Support Communities. We understand you want to delete your music library all at once. We’ll be happy to help with this.

What device are you attempting to do this one? If you have access to a computer with iTunes or Music, you can select multiple songs there and then delete them all at once:

Delete songs and other items in iTunes on PC

Delete songs and other items in Music on Mac

If you’re on an iOS device, you will have to delete them one by one. 

We hope this helps. Take care.