The default window manager provided by KDE is the K Window Manager (KWM). Please read "The K Window Manager Handbook" (should be accessible from KDE Help) for usage information.
Yes, there are some shortcuts for the most common operations.
Invoke the "Current Session" manager.
Traverse the windows on the current desktop.
Traverse the virtual desktops.
Execute command.
Popup the window operation menu.
Close active window.
Switch to virtual desktop.
Destroy window mode.