@asif Sir g there r diffrent trek goes to Pharila,Here i tried to give u some idea.we took the longest route because v de-tracked it took around 4 hrs to descend back to sharda from pharila.
From Shahdra Bridge go to FG Boys School Shahdara and follow dry Nullah and stick with this route u can ask locals from pharilla as u can see lot of locals on way.I mention the trek wihch we followed on descend.