Not living together since 3 years

I am from Bihar and we were living in Pune. As I did not wanted to live with my Husband because he could not believe on me after staying together of 7 years and believing on wrong accusation made by my father-in-law and mother-in-law and fighting each time in the house for wrong reasons and I had a girl child who has started to see our fight, I had asked him to leave the house and after multiple fights, he left the house. He tried to convince me that he has changed now and problems will not be there, when I asked him to come at my place, He did not come and did not come to visit her daughter even after 3 years. Neither he supported financially in any way. He was earlier ready for Mutual divorce but not ready for giving the divorce nor ready to come. I have not applied for divorce yet as this process takes a lots of time. So How I should proceed with divorce process and how much money it will take?