For parking mode you would need to wire the power wire (usb cable) to a circuit that is on all the time when the car engine is off such as the battery. Dashcam usually run off 5v which means you need to use a converter (12v to 5v hardwire kit) which you say have. You connect your dashcam to the converter and then that wire connects to a 12v soruce such as the battery positive terminal. Then the other wire to a ground. For parking mode you need to program the dashcam to trigger the recording when parked otherwise it will drain the battery since it will keep recording all the time when the car is on or off.