To use the trackpad, place one of your fingers on the surface of the pad.
As you move your finger along the trackpad surface, you should see the mouse cursor on your computer screen moving according to the movement of your finger.
Figure 1. One-finger movement
To perform the equivalent to a left-click on your mouse, you can either press down the left side of the trackpad until you feel a button-like click, or tap the surface of the trackpad anywhere with your finger.