Do I charge the gimbal/camera? It has a micro usb port on it, but I'm not sure what it's for? Does the gimbal/camera get power from the battery? Thanks!
You don't charge the gimbal - it is powered from the main battery.
The USB socket is for the slow and complicated way of getting your photos.
It's much faster and more convenient to just pull the SD card, put it in an adapter and copy that to your computer.