Hi @wen yao
After you install the Windows Server Update Services (WSUS) server role on your server, you need to properly configure it. You also need to configure your client computers to receive their updates from the WSUS server.
Configure WSUS
https://learn.microsoft.com/en-us/windows-server/administration/windows-server-update-services/deploy/2-configure-wsus
Here is a thread as well which discusses the same issue and you can try out some troubleshooting steps from this and see if that helps you to sort the Issue.
Why are not there windows server 2022 patches in WSUS?
https://learn.microsoft.com/en-us/answers/questions/658736/why-are-not-there-windows-server-2022-patchs-in-ws.html
Hope this resolves your Query!!
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