This is the code but for some reason, when (distancia<100) the ("ALTO") still appears, and the same with the other while loop
while (distancia<200 && distancia>100)
{
    lcd.print("ALTO");
    delay(1000);
    lcd.clear();
    delay(1000);
  if(distancia<100)
  {
    break;
 }
}
 while(distancia<100)
  {
    lcd.print("INTRUSO EN");
    lcd.setCursor(0,1);
    lcd.print("LA PUERTA");
    tone(11,700,250);
    digitalWrite(8,HIGH);
    delay(500);
    lcd.clear();
    digitalWrite(8,LOW);
    delay(500);
    if(distancia>100);
    {
       break;
    }
}
}
 
                        
this is your while loop:
and this is your if:
a variable can't be greater and smaller than 100 at the same time so that if is basically useless