Its not about pakistan its about the Rule and by Rule Dirt Bike and Daul sports are allowed on Highways, roads, street but "NOT ALL DIRT BIKES"
like for Dirt bike Line up of Honda :
CRF - L/M are Road legal rider Daul sports/ Offroad applicable
CRF - X are for motoCross and not road legal
CRF - F/R NON road Legal Dirt tracker
So when you buy you will have to ask for Road legallity.
Most Non Road Legal dirt bikes can be identified by no front/tail light, no indicatorym, knobby tyres, low top speed high accelration, smaller feul capacity and the list goes on...