The T570NZKAEUC is a Wifi and the T575NZKAEEC is an LTE. This means that the T575NZKAEEC can have a sim card installed like a mobile phone. All the previous answers are not correct. Android 12 is automatically loaded if it is not already installed.

T570 has WLAN / T575 has WLAN and 4G
The letters at the back probably have to do with software version, country code, enterprise or not enterprise.

Looks like the firmware version. Android 12 may stand for T575NZKAEEC?