Keyboard' not found. error

I want to add a windows key to my buttib pres but I get this error message:
Arduino: 1.6.6 (Windows 10), Board: “Arduino/Genuino Uno”

C:\Users[USER]\AppData\Local\Temp\arduino_d35f905a4032897f9105e20889ab986a\Spotify.ino: In function ‘void setup()’:

Spotify:17: error: ‘Keyboard’ not found. Does your sketch include the line ‘#include <Keyboard.h>’?
Keyboard.begin();

^

exit status 1
‘Keyboard’ not found. Does your sketch include the line ‘#include <Keyboard.h>’?

This report would have more information with
“Show verbose output during compilation”
enabled in File > Preferences.

const int next = 13;
const int pause = 12;  
const int pref = 11;  
#include <Keyboard.h>
const int rood = 10;
const int groen = 9;
const int oranje = 8;

int nextState = 0;
int prefState = 0;
int pauzeState = 0;       

void setup() {
  buttonSetup();
  ledSetup();
  Serial.begin(9600);
  Keyboard.begin();
}

void loop() {
  nextState = digitalRead(next);
  prefState = digitalRead(pref);
  pauzeState = digitalRead(pause);

  deIf(nextState,groen);
  deIf(prefState,oranje);
  deIf(pauzeState,rood);



}
void deIf(int state, int led){
   if (state == HIGH) {
    digitalWrite(led,LOW);
  } else {
    digitalWrite(led,HIGH);
  }
}

void buttonSetup(){
  for (int i = 10;i < 14; i ++){
    pinMode(i,INPUT);
  }
}
void ledSetup(){
   for (int i = 7;i < 11; i ++){
    pinMode(i,OUTPUT);
  }  
}

Have you bothered to look at the documentation for the Keyboard library? It is NOT available for all Arduinos.

Nope I just starded trying, I have the arduino UNO do you know an other way to do it?

do you know an other way to do it?

Sure do. Get an appropriate Arduino.