bool lastBtnState;
bool ledState;

void setup() {
  pinMode(10, OUTPUT);
  pinMode(7, INPUT_PULLUP);
}

void loop() {
  bool BtnState = digitalRead(7);
  
  if(BtnState != lastBtnState){
    if(BtnState == LOW){
      ledState = !ledState;
      digitalWrite(10, ledState);
    }
    delay(100);
  }
  lastBtnState = BtnState;
}