Funny, i can only see this case - good looking btw. - sold in scandinavia.
The first picture shows, by my interpretation, and RGB controller, controlling the colour of your fans, and the "color changing mode", and, perhaps, it also provides power to the fans, so without they might not run at all.
Your second picture shows the plug to connect it to your Power Supply Unit (PSU).
Example are here, it is to be conneted by the "4-pin peripheral power cable" or "molex cable":
http://www.playtool.com/pages/psuconnectors/connectors.html
https://www.pcinside.info/inside/inside-power-supplies/power-supply-cables-connectors/