To use the extended desktop:
Open the window or program you would like to display.
Click on the top panel of your window and drag to the right side of the monitor, keep dragging over until you see the entire window on your extended display.
To make a window full screen, drag towards the top of the display.
Drag as many windows as you would like back and forth between the two displays. Control them all at the same time by moving your mouse between displays.
For further help and questions, you can submit a ticket at support.northamptonma.gov