The organs involved in the Nervous System are: Brain, Nerves and Spinal cord.
The Nervous System is the one that control almost all the muscles like when you are moving your hand the Nervous System is the one that control that and the function is to think and give a response.
General info of the system
Tim Barclay. (2020). Nervous System. 20/04/2020, de innerbody Sitio web: https://www.innerbody.com/image/nervov.html