The "002" prefix suggests it is the second file in a sequence, likely generated by a camera system, a screen recording tool, or a batch processing script.
Because the name is randomized, it is often used to prevent people from guessing the file's location or content without a direct link. 002_Gj5KhoWd77yQLUth.mp4
Do you have any on where you found this file name or what the video content actually shows? The "002" prefix suggests it is the second