Hello everyone. I am quite new to photography, but I have been making youtube videos for a while, and I was wondering; What exact advantages does photo have over video?

When I create my thumbnails, I usually make a video, and then select 1 frame from the video as a 'photo' for the thumbnail. I am willing to step up my game and take actual photo's, but what exactly is the advantage of photo over video? As far as my knowledge goes right now, everything that I can do in photography mode (set aperture, shutter speed, etc etc), I can also do in video mode, and it's much more practical to take a video from myself than a photo.