Transferring songs from iTunes Library ti iPod

I recently purchased a new iPod 6, my old one was showing signs of age. I have songs in my iTunes library that are not transferring or syncing to the new iPod. I have tried everything but they just do not transfer. Any ideas would be very helpful. Also, the new iPod keeps saying that iCloud needs to be "Enabled". No matter how many times I enable it, I still get the same notification.