I think you should start by reading through the help content in SCM, key sections for new users include:
How to perform common tasks
Working with SCM
You should also read the security guide for each product that interests you, so for Windows Server 2008 open SCM, expand Microsoft Baselines in the Baselines Library, then expand Windows Server 2008 SP2, and select the Attachments\Guides folder. You can
save or open the document, Windows Server 2008 SP2 Security Guide, from that location.
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