How can I initiate a divorce if I suspect my wife of adultery

My uncle who is marriage broker was went to my wife's house in ashadam and invited her alone to his home. Her mother replied him how she 'll come alone for long place ? She will come along with her husband . He replied immediately that ohhh...you want to come that way uhhh...Here no one objected his words what way he likes her to come ? One day Myself wife and my father went to my uncles house for discussion on dispute. He discussed with me for 1 hour along with my father. After he discussed with my wife alone for 1.5 hours closed 6 doors . Father and my self went and opens the door they are not in room. searches whole house except one room which locked inside and swith off lights. After half hour they come called us again uncle started discussion and fought wid me by supporting wife. I asked my wife where u were ? She said we are another room seeing house which shealready seen for 1 hour. Who will show room by locking and swithoff lights? Can i ask for narco test and divorce?