Hi, @PAVZ
Thank you for posting in Microsoft Q&A forum.
To manage workgroup computer in SCCM, we have to install client agent on the computer first. Then deploy software updates to the computer like domain client.
Here is the detailed steps to install SCCM client agents on workgroup computers:
https://www.prajwaldesai.com/install-sccm-client-agents-on-workgroup-computers
(Please Note: Since the website is not hosted by Microsoft, just for your reference.)
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