Programming a hold button using multiple inputs

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6

Hey, thanks for the restating of the issue.
not tested but presenting a possibility

void setup() {
  // put your setup code here, to run once:

}

unsigned long qaz = millis();
int onDuration = 1000;
void loop()
{
  if ( digitalRead(swt1) == HIGH && digitalRead(swt2) == HIGH )
  {
    //start timer to make LED's stay on when both switched are pressed.
    qaz = millis();
    digitalWrite(led1, HIGH);
    digitalWrite(led2, HIGH);
  }

  if (  millis() - qaz) > = onDuration )
  {

    if (digitalRead(swt1) == 0) {
      digitalWrite(led1, HIGH);
    } else {
      digitalWrite(led1, LOW);
    }

    if (digitalRead(swt2) == 0) {
      digitalWrite(led2, HIGH);
    } else {
      digitalWrite(led2, LOW);
    }

    if (digitalRead(swt1) == 0 && digitalRead(swt2) == 0)
    { digitalWrite(led3, HIGH);
    }
    else {
      digitalWrite(led3, LOW);
    }
  }
}

Oi! as written the code may mess with the 1st second of operation.