if u go by bus, u can't visit many places there... kallar kahar is hell bundle of places to visit. and if u just want to visit kallar kahar lake or near by things then u should choose bus,,
route depend on your conveyance,,
bike route is ,, Lahore to GT Road till Gujrat,,> turn left towards > dinga > Pindi saidan shah ? pind dadan khan > khewra salt mines > katas raj temples > kallar kahar...
u can choose route from sargodha too ,, but its lengthy,