Divorce / marriage counselor

I am married in the year 2016, everything was fine till one month of my marriage, thn my mother in law started saying me words in directly, saying That I might Seperate her son from her , I tried to make her understand she acts OK with me and tells my sister ( my brother in law's wife) everythung negative about me and created distances in relations. I don't know why is she like that, I gave birth to girl child in 2017, even at that time she's not happy and created a fight between my husband and me and my mom. My husband speaks to abusevly every time. He blackmails me I will say all negatively about your mom and sister to everyone if you try to say back answers, what ever I say you have to listen. He said he owns a business at the time of marriage but later it went into losses and from 2017 till date he doesn't do any job neither he wants to do a job, he has completed MBA. All the time he says he only wants to do business. Now he is asking for my certificates to get loan on certifucates. I don't hope Tht he will run the business properly Becoz he says this all the time from 2017. My in-laws belong to harijan caste, They didnt say this before marriage , I belong to Brahmin family. Ours is arranged marriage, whatever I try to ask my husband shouts and uses abusive language and try to blackmail, Infrnt of everyone he acts so well as if I am the world to him but he never treats me Gud. He says I will give you divorce all the time and blackmails me saying if you ask for child custody then he will murder me and my mom and my Sis and he will sit in prison and within 2 days he will get the bail. Even my brother in law doesn't work and he married a girl in 2017 saying he is a doctor, later the girl and her family got to know that he don't even complete his 12 th standard and he doesn't work, she went away to her parents home with her children. Pls let me know wha should I do. I want my child custody