Inheritance Distribution

My father expired last month due to sepsis after an operation in Bhopal. He did not leave a will. He has properties and FDs in Bhopal and Inherited properties in a village in Uttar Pradesh. He left behind 5 children (4 daughters + 1 son) and a wife. My brother's family and my mother lived with him in a house also owned by my father in Bhopal. I have following questions: 1. Who has the authority to sell his properties? What will be the process to sell his properties? 2. What can be done about his bank accounts and FDs? He did not leave a nominee's name in any of those. 3. Can my brother sell it without the sisters' presence/approval? 4. Does my mother have the authority to sign the sisters' share to the brother? 5. Is there any work-around/ loophole that my brother can use to take over the sisters' shares? 6. What is the process/documents if a sister wants to let go of her share? Also, about the cause of my father's death, I am very suspicious that there was negligence from the hospital's side. They did not take timely note of his early signs of sepsis that led to his death. What can I do to file a negligence case against the hospital? What documents will I require?