int buttonPin = 2;
int ledPin = 13;   
bool buttonState = false;

void setup() {
  pinMode(ledPin, OUTPUT);    
  pinMode(buttonPin, INPUT);  
}

void loop() {
  
  buttonState = digitalRead(buttonPin);
  
  if (buttonState == HIGH){
    digitalWrite(ledPin, HIGH);   
  } else {
    digitalWrite(ledPin, LOW);   
  }
}