Hello TracepPL,
Thanks for the additional details. If the songs were manually synced to the device through iTunes on a computer, then the only way to get those files on the new phone would be to connect it to whatever computer has those files on it.
If you have a new computer, you can migrate backup and move your iTunes Library with these steps: Back up and restore your iTunes library on your PC
If it's a Mac, you can use Migration Assistant to move the iTunes Library over: Move content to a new Mac
If you no longer have access to the computer that has these music files on it, then you would need to re-import those CD's to the computer you're currently using now and then sync them to the phone.
You can also use the Apple Music service, which gives you access to Apple's full catalog of music if you're trying to avoid manually syncing with a computer all together: Apple Music
Cheers!