Hi @maciek,
1. Yes. By default, spacedesk Server starts automatically upon Windows start up. You can check this via spacedesk Driver Console -> Control, on Configuration box where you can find the “Automatic Start at System Boot Time” check box.
2. Yes, just download the spacedesk Windows 7 Viewer (version 0.9.39) on your laptop.
Just make sure to check the Keyboard and Audio Speaker on Functionality settings before connecting it to your Primary PC.