int button = 4;
int ledR = 5;
int ledG = 6;
int ledDelay = 300;
int m = HIGH;
unsigned long changeTime;

void setup() {
  pinMode(button, INPUT_PULLUP);
  pinMode(ledR, OUTPUT);
  pinMode(ledG, OUTPUT);
  changeTime = millis();
}

void loop() {
  if((millis() - changeTime) > ledDelay){
    m = !m;
    changeTime = millis();
  }
  if(digitalRead(button) == LOW){
    digitalWrite(ledG, HIGH);
  }
  else{
    digitalWrite(ledG, LOW);
  }
  digitalWrite(ledR, m);
}