Good morning BlackSnow21!
It sounds like you transferred over your music to your new iPod, but you’re missing a song and want to make sure you’re not missing any other music. I’ll be happy to help out.
Was the missing song purchased? If so, follow these steps to redownload purchased music: Redownload apps, music, movies, TV shows, and books from the iTunes Store, iBooks Store, and App Store
If you’re using iCloud Music Library with Apple Music to sync your songs over to your new iPod, then you’ll want to follow these steps instead:
If songs that you bought are missing or the song names appear in gray text, they might use digital rights management (DRM). You need to authorize your computer before you can play these songs.
After you authorize, choose File > Library > Update iCloud Music Library from the menu bar at the top of your computer screen or the top of the iTunes window.
If you synced the songs that appear with gray text to your iOS device from a Mac or PC, turn on iCloud Music Library on that computer and your library should update.
Get help with iCloud Music Library - Apple Support