In game when I press a button on my keyboard it will start a countdown on a timer until it hits zero. Is this something that is possible to make in blender game engine?
Yes, easily through logic bricks and using a text object.
In this example, the property
start rules if the countdown is started. When Spacebar is pressed
True, then the
Text property gets decreased each 60 frames (that is, 1 second).
Example blend file provided below.