iCloud Sign-In Problem on iPod Touch (4th Gen)

I have a 4th Generation iPod Touch I just restored using my iMac running Catalina (10.15.2). My iOS on the iPod touch is now 6.1.6. I cannot sign into my iCloud account because I am not able to enter in a verification code after entering in my iCloud username and password. Could anyone help? Or, does anyone know if I just cannot use my iCloud account on this device because it's so old? Thanks in advance for your help.