Regarding Motor Accident

The person A is going in his way using his bike. The person B is tries to cross the road and suddenly he hits the bike of person A. Here there is no issues on the person A. Due to the negligence of person B, this accident happened. When person B hits the bike, he fell down and got head injury. After that person B is admitted to the hospital. On the duration of the accident, the Person B is not in the influence of drugs or alcohol. The Person B mistakenly raised the accelerator when crossing the road. Due to that, Person B's bike suddenly hit Person A's bike. Person A's bike got damage on right side of the bike. Person B's bike got damage on front of the bike. Person A didn't get any injury in this accident. Person A only called the ambulance and helped Person B after he fell down. During the medical treatment of person B, Person A filed the police complaint against Person B and stating that the accident happened due to negligence of person B. Police filed the IPC 279, 337, 338 against Person B. After the day after the accident, Person B died during the medical treatment. Here the Person B details are: Age: 50 Work: Building Contractor Both Person A and B have a valid license and insurance for their bikes. In this case what will happen next? Will the IPC 304(A) added to the FIR? Can the person B's legal heir, register the MCOP case in MACT? What will happen to person A?