Testing with external RAN/UE, would you pls share how to add ue data in UDM (mongodb) with mongodb cli command

Hi,
I get to know from another post that when testing with external RAN/UE, AMF cannot get subscribe data of UE from UDM, we need to insert a subscriber (UE data) before running the test. I don’t have access to free5gc web UI, would you pls tell the detailed mongodb cli command to add ue data in UDM?

I only know this mongodb command:

show collections

Thanks a lot!
Br,
Andrew