What is the part called that controls the dash and tail lights?

All the bulbs and fuses are new. Someone told me it's the Multi-function switch or Headlite switch ??? They said it's a dealer part or I can look on line and it would be cheaper. Do you know how much it is and if I can put it in myself. The part foes along with the turn signal handle and connects into the stering wheel colum. Thank you.