CAN Interfacing with Pixhawk

Hi I am Developing a ESC( Motor controller ) which is having CAN2.0 interface and PWM input. i want to make the CAN Communication between ESC and Flight controller. the flight controller i am using is pixhawk 2.4.8. what is the CAN ID i have to use while sharing the message from ESC and What is the data format i have to use. also please what is the configuration i have to use in the mission planner.
i am new to this flight controller.
please help me to communicate with this flight controller from my ESC.