int button = 3; 
int led = 7;
int buttonState = 0;

void setup() {
  
  pinMode(led, OUTPUT);
  pinMode(button, INPUT);
  digitalWrite(buttonPin, HIGH);
}

void loop() {

  buttonState = digitalRead(button);

  if (buttonState == HIGH) {
    // turn LED on:
    digitalWrite(led, HIGH);
  } else {
    // turn LED off:
    digitalWrite(led, LOW);
  }
}