I upgraded a couple of camera's firmware. Check out the instructions for your camera at Nikon, because I am not sure how to do it for the D3200 but it is probably similar to what I did. Format the memory card on camera, download the firmware file and upload it to the memory card and put it in the camera. Turn on the camera and It prompts you to update or whatever. I use firefox pretty much exclusively so I dunno about Chromebook.
Rob