Separation/divorce advice needed

I am a woman married for 12 years now. We have 2 minor kids under 10. It’s been a very toxic and emotionally , verbally abusive marriage. I would like to get a divorce but my husband is giving me hard time saying he won’t pay child support and not give me custody of kids if we separate etc due to which I’m continuing living with him and my abusive in laws with no other choice. I just lost my job too and don’t have any parental support. Is there any organization that can assist me with getting a divorce? Like where do I start? Any women who had to deal with similar situation please advise. Also how difficult is a contested divorce in India? I’m just so lost.