Hi, @Menta Elise
Thank you for posting in Microsoft Q&A forum.
To update SCCM from version 2203 to 2303 using the "Updates and Servicing" in the console, you need to ensure that your service connection point is in online mode. Then, use the "Check for Updates" option in the "Updates and Servicing" node to force a check.
If your service connection point is in offline mode, use the service connection tool to manually sync with the cloud service.
If you still cannot find the update, your account might lack the correct role-based administration permissions to view updates in the Configuration Manager console.
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