go to the Office installation folder, i.e. "C:\Program Files\Microsoft Office\Office16", confirm the "OSPP.VBS" file is existing

open CMD in administration mode, cd to the above path

execute this line to list all installed license

cscript ospp.vbs /dstatus

example output:

---Processing--------------------------
---------------------------------------
PRODUCT ID: 00405-32240-48001-AAOEM
SKU ID: 480df7d5-b237-45b2-96fb-e4624b12040a
LICENSE NAME: Office 19, Office19HomeStudent2019R_OEM_Perp edition
LICENSE DESCRIPTION: Office 19, RETAIL channel
BETA EXPIRATION: 1601/01/01
LICENSE STATUS:  ---OOB_GRACE---
ERROR CODE: 0x4004F00C
ERROR DESCRIPTION: The Software Licensing Service reported that the application is running within the valid grace period.
REMAINING GRACE: 29 days  (43196 minute(s) before expiring)
Last 5 characters of installed product key: 76FRV

get the installed product key: 76FRV

to uninstall

cscript ospp.vbs /unpkey:76FRV