Roughly what you want is to position the head of the driver at a specific location. By filming drivers from the side you could locate the head with a standard neural network and move the seat accordingly. If you want to locate the eyes specifically you’ll also need to film them from the front, but position of the head alone should be close enough. An inexpensive Raspberry Pi with camera should indeed do the trick, though you may not have enough computational power to run a neural network. Edge Development boards could be better fitted.