You have not explained what you actually want to do, but to attempt to reverse engineer a device like that, as a novice, is not a good way to start any project.
If you want to use an Arduino compatible infrared, non contact temperature sensor, I suggest to get the MLX90614 individual sensor, or the Grid Eye 8x8 thermal camera.
If you carefully follow just about any of the many tutorials on line, they will work right away.