The windshield washer fluid reservoir on a Peugeot 106 is typically located in the
engine bay, usually towards the
front and often
on the passenger side. It's a fairly small, plastic reservoir, sometimes translucent or clear so you can see the fluid level. Look for a cap marked with a washer fluid symbol (often a windscreen with jets spraying). It might be near other fluid reservoirs like the coolant or brake fluid.
Because the exact location can vary slightly depending on the year and model of your Peugeot 106, it's best to consult your owner's manual for the precise location. A quick online search for "Peugeot 106 washer fluid reservoir location" along with images may also help you identify it visually.