How to file a complaint for medical negligence?

I have only 15 days left to file a complaint regarding my mother’s passing due to medical negligence during her angioplasty. Despite our requests, the doctor informed her about the surgery inside the OT, causing extreme panic, which I believe contributed to her death. She was supposed to be shifted to the ICCU but was placed in the ICU due to a lack of beds. Her monitor displayed another patient’s name, raising concerns about overall negligence. After her passing, the hospital provided an unexplained 50% bill discount, which felt like an attempt to silence us. The surgeon left immediately after the surgery for a flight, abandoning her critical care. The hospital delayed releasing her body and initially left the cause of death blank on the certificate. The risks of the procedure were misrepresented, making us believe the surgery was low-risk. I do not seek compensation—just accountability, better medical practices, and justice. What steps should I take next? Will this case get the attention it deserves?