Does Windows Remote Desktop lock or hide the screen of the remote PC?

The screen is locked and it will show who is logged in remotely, as well as the hostname of the remote computer. When you log off it remains at the logon screen. More than one person cannot be logged in simultaneously.

I can't test this since I only have 2 PCs, and they're not at the same location.

You can, use VNC.

eg.

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