Good day. Thank you for your question.
The Odometer values can be inserted in the Odometer value(km) tab and the device will start calculating from that value. However, if the vehicle does not broadcast the odometer via the OBD port then you will need to use another source - GNSS. Please go through this link for more information - https://wiki.teltonika-gps.com/view/FMC001_Trip/Odometer_settings#Odometer