#define LED 45     // D1(gpio5)
#define BUTTON 48  //D2(gpio4)
//Let's say you have your push button on pin 4
int switchState = 0; // actual read value from pin4
int oldSwitchState = 1; // last read value from pin4
int lightsOn = 0; // is the switch on = 1 or off = 0
int debounce = 20; //is the noise from switch

void setup() { 
 pinMode(BUTTON, INPUT); // push button 
 pinMode(LED, OUTPUT); // anything you want to control using a switch e.g. a Led
}
void loop() {
  switchState = digitalRead(BUTTON); // read the pushButton State
  delay(debounce);
  if (switchState != oldSwitchState) // catch change
  {
    oldSwitchState = switchState;
    if (switchState == HIGH)
    {
      // toggle
      lightsOn = !lightsOn;
    }
  }
  if(lightsOn) {
    digitalWrite(LED, HIGH); // set the LED on
  } else {
    digitalWrite(LED, LOW); // set the LED off
  }
 }