Help me help my mom get out of an abusive relationship

My mother has been with my step dad for over ten years. The relationship is okay until I visit them. It is like my visiting my mother sparks the abuse. Recently, I was visiting my mother then decided to go see my grandmother, but i forgot my phone at my mothers house. My father called my mother to check if I was alright and to ask for my grandmother's phone number. My step father was enraged by this contact my dad made with my mother. A physical altercation ensued and the man pushed and shoved my mom a couple of times and attempted to hit her with a metal rod that he found around the house. luckily he was stopped.

I mean this man would not let my mother attend my paternal grandmother's funeral and support me on the day even though my paternal grandmother took me in when I was four months old and she was my world and had made it possible for my mom to go back to high school after giving birth to me.

My step dad has used the money that they were meant to buy a house with to pay the debt of his own family without consulting my mom. They are currently staying in someone else's government subsidy home they are renting and the person lives outside in a shack.
These are examples of some of the abuse my mom endures because of the power imbalance in that relationship.

My mother works for minimum wage and he earns more but somehow carries most of the financial burdens. She is tired and wants a divorce.

Funds raised will be going towards buying a home and paying school fees for my siblings while my mom tries to get a better job. Sometimes in winter when we need to relieve ourselves outside in the cold using bucket system toilets, my mom remarks that the day she sits on a toilet in her own home will be the best day of her life.

please help me give her a home and assistance following this divorce.