iPhone 11 not showing in music

With all the updates to my iMac, macOS Catalina 10.15.2 and iPhone 11IOS 13.3, I cannot figure out how to add music to my iPhone 11. It used to be so easy by opening iTunes, choosing my iPhone and syncing music. Now my iPhone does not show in the new version called Music. I have gone into System Report and made sure my iPhone is listed under USB. Guess I've gone brain dead.