Hi yogeshwaran,
Thanks for your posting.
To avoid the deviation of understanding, I have the following understanding need your assistance to confirm:
You want to implement the following features: The WSUS Server approves the updates for the client and then the client installs the update at a specified time. It is possible that the following Group Policy will enable this functionality:

I'm not very proficient at Powershell, but I'll do more research on this issue. If there is any follow-up, I will let you know at the first time.
Regards,
Rita
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