Domestic Violence by my elder brother on my parents

Hello sir/madam, I live in Indore and my father is retired senior citizen aging 63 and my mother is 57 years old. My elder brother who is 35 married from last 3 years. My dad has provided all the necessities from education to a upper middle class life to all of us being a banker. My brother has completed his graduation, left MBA in middle and completed a private certification course all by his choice and expenses were beared by my father. He got a few jobs but left in a few months due to his own choices and struggles. Until today he is not earning a single penny and totally dependent on my father. Above all, he rules their lives and in case of any interruptions from my side or parent's questions about anything he abuses all of us. He crossed all of his limits and threatening to kill us or commit suicide. Since last 12 + years after his graduation and job, we are trying to help him out in all possible manners but he is overruling all of us, his anger is out of control, he abuses on roads, in house for hours and hours. He is mentally torchering my father, mother, my younger sister too. Somehow we have completed his marriage, that was love marriage and he ruled the entire process according to him and for the sake of his happiness and looking towards simple behavior of my father, I was unable to interrupt much on anything. After his marriage, he even tried hitting my dad in front of his wife, he abuses every other day, he wants all luxurious life and noone can interfere in that. I dont want to comment much on my bhabhi but she is also on his side and behaving disrespectfully to my parents. She is driven by her own desires, we can not question her for anything otherwise my brother will come and fight for hours. Me and my younger sister work in different cities and whenever we visit home on any occasion or leaves, they blame us for everything, pressurizing indirectly to not to come home. Situation is in very bad condition, someone will commit suicide at my home, m helpless to leave my parents like this. They dont leave the home and every day he is abusing my dad for hours, blaming for all of his failures, using such words that are enough to kill anyone's soul, fighting with us. He even tried hitting my father. In past, on a regular basis, he used to throw shoes or anything on my mother and sister when my father was also posted in other city. There are so much to say that has happened in 12 years, in last few years I tried using internet and reached out to few counsellor via telgram and all but was worried that my family will break, it is tough for my father and mother to take any legal action against their own son. I came home after more than a year to avoid issues because of me being at home but I came due to lockdown to see my parents. This time I cant resist looking at the situation, the domestic violence that is happening with them. I do not want any actions against him, he is my brother but I want my parents to take away from him. He is financially dependent on them and he does not leave or let them leave with me. My bhabhi is taking full benefits out of this situation but I dont want to blame her for anything. When my father told him to leave otherwise he will take legal support, he is threatening for false dowry case. He is threatening to kill me, sometimes he is threatening to commit suicide and screw our life and other days he is threatening to abuse every day in front of relatives to everyone. I need the guidance on what should I do? He is not a support to anyone financially, emotionally, physically or in any sense and above all we all are suffering because of him.