Microsoft has retired the Windows Home Server product line. Really annoying since I use it extensively. Only choice now for same backup support and Windows 8+ support is to go with Server 2012 Essentials which I am in the process of installing.
To address your issues...
BACKUPS: Forget it. You won't see a backup client. There are some nice Amiga utilities to do backups for you. Look at Aminet and also os4depot.net. There is even an S3 client to sync your files to Amazon storage if that floats your boat.
FILE SHARING: You should already have some shared folders on your Home Server set up by default. These will be visible to other PCs in your household. To make these visible to your Sam you will need a SMB/SAMBA client set up to access these shares. I am not sure on the state of the SMB support. Your success may also vary based on the version of Home Server you are running as the protocols have evolved with newer versions of Windows and I don't think the Amiga SMB support has kept up.
Hopefully others will pipe in with more info on backup utilities and more SMB info.
Cheers!
