Functions? Creating a Radio Hub

I tried to simplify my code. I think I need to do a few things. Maybe make the ScreenTwo= LOW and lcd.clear() stuff a function to clean up everything, or put the millis stuff into the ~~ I feel like something should go here ~~ part.

Helping a novice like me, probably seems grueling, but I really appreciate all your help!

unsigned long startMillis;
unsigned long currentMillis;
const unsigned long ScreenRefresh = 5000;

void loop(){

  currentMillis = millis();


  if (customKey == '*' ) {
    currentMillis = millis();
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("The Coop Door Is");
    ScreenTwo = HIGH;
 
~~Feel Like Something Should Go Here ~~
    
    ScreenTwo = LOW;
    lcd.clear();
    MainMenu();
    }
  }
 
 if (ScreenTwo == HIGH)  //if we are showing screen 2
  {
    if (currentMillis - startMillis >= ScreenRefresh)  //if the period has passed
    {
      CoopDoor();  //refresh the screen
      startMillis = currentMillis;  //save the time that it was refreshed
    }
  }
}

So maybe something like this?

unsigned long startMillis;
unsigned long currentMillis;
const unsigned long ScreenRefresh = 5000;

void loop(){

  currentMillis = millis();


  if (customKey == '*' ) {
    currentMillis = millis();
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("The Coop Door Is");
    ScreenTwo = HIGH;
  
    }
  }
 
 if (ScreenTwo == HIGH)  //if we are showing screen 2
  {
    if (currentMillis - startMillis >= ScreenRefresh)  //if the period has passed
    {
      CoopDoor();  //refresh the screen
      startMillis = currentMillis;  //save the time that it was refreshed
      ClearScreen();
    }
  }
}

void ClearScreen (){

    ScreenTwo = LOW;
    lcd.clear();
    MainMenu();