They have either Bendix or Girling brakes - depending on whatever mood Peugeot were in at the time.

The front pads are distinctly different shapes, so get a good look at them (or take a few pics on your phone) before you go to buy replacements.

There isnt really 1 which is more common than the other on 106's.

If you want discs = remember to check if theyre 3 or 4 stud wheel fitment.

IIRC, on the rear you can check the shape of wheel cylinder casting that goes through the backplate - so you can see it from underneath the car.

Round or oblong, your motorfactor should know the difference (i cant remember which is which )

106's dont wear out rear shoes very often, but sometimes the linings come off.