Procedure to lodge fir against doctors under section 304 part-ii

My wife was suffering from disease of multiple fibroids in uterus and hence was admitted to get her uterus removed. she had undergone two caesareans during delivery of our two children. doctors advised us to get the uterus removal done through laparoscopic technique which is actually not advisable in this case (as turned out later on). They assured us that this is better method as compared to open surgery and convinced us to get it done.My wife was got operated through laparoscopic technique on 01.10.2018 and the duration of surgery was almost 04 hours. since after operation she was in critical position (who earlier before operation was fully healthy/fit), urine output was nil, she was facing acute pain etc, their was no qualified doctors and equipments in the so called icu, her both kidneys and other important organs were not working since after operation but neither concerned doctors have arranged specialists doctors even after lapse of 24 hours nor intimated us the failure of kidneys and other organs on the following day in the afternoon doctors have asked us to shift the patient in dmc Ludhiana on the ground of failure of kidneys and other organs we shifted her in very critical position where she died on the same day. my wife who was only 46 years old demised only due to gross negligence by adopting wrong method of surgery as well as hiding the facts after operation, due to non availability of post operative measures, not disclosing the facts timely etc. they are liable of punishment under section 304 part-ii, kindly suggest procedure to lodge fir etc