int LED = 8;
int buttonPin = 7;
void setup() {
  pinMode (7, INPUT_PULLUP);

  pinMode (8, OUTPUT);

}

void loop() {
  
  if (digitalRead (7) == LOW){

    digitalWrite (8,HIGH);
    delay(100);
    digitalWrite (8,LOW);
    delay(100);
  }
  else
  {
    digitalWrite (8,LOW);
   }

}