Q. How do I transfer music from my old iPad or iPhone to my new one?

iTunes
A. If you bought all of your music from the iTunes Store and downloaded it directly to your old iPad or iPhone, you can use the iTunes Store app on the new iPad or iPhone to download all your past purchases again to the second tablet. You need to be logged in with the same Apple ID account you used to make the original purchases, or be set up to use the content with Apple’s Family Sharing feature.
To download songs again, open the iTunes Store app and tap the Purchased icon at the bottom of the screen. Tap the “Not on This iPad/iPhone” button to see a list of all your past iTunes purchases. Tap the cloud-shaped Download icon next to each song you want, or the Download All Songs button at the top of the screen to grab the whole collection.
If you have been using Apple’s iTunes program on your Mac or PC to copy music to the old iPad or iPhone, you can sync the same music library to the new tablet. Just connect the new iPad or iPhone, select its icon when it pops up in the iTunes window and click the Music icon. In the main part of the iTunes window, check the Sync Music box, click the Apply button and then the Sync button. Songs from the iTunes Store that were bought on the iPad or iPhone can also be downloaded again to the computer, and you can use iTunes (or Apple’s iCloud service) to transfer other files by backing up the old iPador iPhone and “restoring” its contents to the new model.
If you have songs on the old iPad or iPhone that did not come from the iTunes Store (or that are no longer for sale there and cannot be downloaded again), you can also use a program like iMazing or Macroplant’s iExplorer to tap into the iPad’s or iPhone’s media libraries and copy the music files back to a computer. Once the songs are on the computer, you can import them into iTunes or your third-party music-management program of choice and transfer them over to the new iPad or iPhone.