Q: how do i find all of my music ive ever purchased

Hi ponsita04

All iTunes purchases are linked to the Apple ID that purchased them regardless of the phone or device.

If you have more than one Apple ID then you will have more than one set of purchases.

Apple IDs cannot be merged, however, you can turn on Family Share and add each of your Apple IDs to the Family Share so that all purchases can be shared.

Set up Family Sharing - Apple Support