I'm thinking you are asking about "brake" pads, as in the brake/stopping system of a vehicle. A Holden, if I remember correctly is an Australian GM built vehicle. This should be moved to the "Automotive Repair" section.
Can someone please tell me how to change break pads?
You should pick up one of those Chilton or Haynes manuals if you're working on the car to get the specifics for your model. There are other things associated with a pad change, especially if it's the front wheels on a rear wheel drive car.
A Holden is a GM, it should work the same way any other GM works.
remove the wheel
remove the rattle guard (that giant clip)
pull out the rubber gromets and use an allen wrench to take out the caliper slide pins
get rid of caliper (put it on an upside down bucket)
yank the pads out.
Find out what the torque specs are before you put it back together though! The caliper slide pins will have a relatively low torque spec.