How do you delete music from the iPhone library?

Hello there, bassvid.

Thanks for reaching out to Apple Support Communities.

The following Knowledge Base article offers up how to delete content from your iOS device:

Delete music, movies, podcasts, and other content from your iPhone, iPad, iPod touch - Apple Support

The particular steps for music are as follows:

About your iTunes in the Cloud content

If you see an iCloud icon next to the item you want to delete, the item is stored in iCloud and not on your device. You can hide (and unhide) these items.

Delete music and audiobooks

Remove songs, albums, or audiobooks from the Music app by swiping to the left and tapping delete.

Kind Regards,

Pedro.