7-Segment Led multiplexed Display with 2 buttons

Hello, I want your help to do this please (I've multiplexed 3 LED's):
One of the two buttons allow you to select the module you want to display (only displayed 1 simultaneously), ie, each press will advance to the next module, considering that there are 3 modules are numbered from 1 to 3. The other button, when clicked, will increase by 1 the value of the selected display to the previous button. The program should remember that value had each of the displays.
-All displays start in first round '0' and when the first round is over, each display will remember their value, starting with that value. For example:
First round [ 0,0,0] We put: [2,5,8] So: Second round will start [2,5,8]
I tried putting how to turn on each display with button 2 (P2) but I couldn't check it, I would fail to do that and to remember the value, I have been told that it works with a vector

int num = 0;
int delayTime;
int counter=1;
int estadoBoton1 = 0; 
int estadoBoton2 = 0;
int P1 = 3;
int P2 = 2;
//Displays multiplexed
int LED1=4;
int LED2=5;
int LED3=6;
void setup (){


pinMode(P2, INPUT); 
pinMode(P1, INPUT);

pinMode(7, OUTPUT); 
pinMode(8, OUTPUT); 
pinMode(9, OUTPUT); 
pinMode(10, OUTPUT); 
pinMode(11, OUTPUT); 
pinMode(12, OUTPUT); 
pinMode(13, OUTPUT);
//Display Multiplexed
pinMode(LED1, OUTPUT);
pinMode(LED2, OUTPUT);
pinMode(LED3, OUTPUT);


}

void loop(){

estadoBoton1 = digitalRead(P1); 
estadoBoton2 = digitalRead(P2); 
Serial.println(estadoBoton1);
delay(50);
Serial.println(estadoBoton2);
delay(50);


 if (estadoBoton1 == HIGH) { 
    num = num+ 1; 
  } 
if (num >= 10){
  num=0;
}
 if (estadoBoton2 == HIGH) { 
    counter + 1;
 }
    //reset counter
    if(counter == 4) {
      counter = 1;
    }
    
  } 
  
 //Change mode
  if(counter == 1)
  {
    delayTime = 250;
  }
  else if(counter == 2)
  {
    delayTime = 100;
  }
  else if(counter == 3)
  {
    delayTime = 50;
  }
  
  //Light show!
  digitalWrite(LED4, HIGH);
  delay(delayTime);
  digitalWrite(LED4, LOW);
  digitalWrite(LED5, HIGH);
  delay(delayTime);
  digitalWrite(LED5, LOW);
  digitalWrite(LED6, HIGH);
  delay(delayTime);
  digitalWrite(LED6, LOW);
  delay(delayTime);
}



switch (num) { 
case 0: 
limpiar(); 
cero(); 
break; 
case 1: 
limpiar(); 
uno(); 
break; 
case 2: 
limpiar(); 
dos(); 
break; 
case 3: 
limpiar(); 
tres(); 
break; 
case 4: 
limpiar(); 
cuatro(); 
break; 
case 5: 
limpiar(); 
cinco(); 
break; 
case 6: 
limpiar(); 
seis(); 
break; 
case 7: 
limpiar(); 
siete(); 
break; 
case 8: 
limpiar(); 
ocho(); 
break;
case 9:
limpiar();
nueve();
}

}

void cero(){ 
digitalWrite(7,HIGH); 
digitalWrite(8,HIGH); 
digitalWrite(9,HIGH); 
digitalWrite(10,HIGH); 
digitalWrite(11,HIGH); 
digitalWrite(12,HIGH); 
}

void uno(){ 
digitalWrite(8,HIGH); 
digitalWrite(9,HIGH); 
} 
void dos(){ 
digitalWrite(7,HIGH); 
digitalWrite(8,HIGH); 
digitalWrite(10,HIGH); 
digitalWrite(11,HIGH); 
digitalWrite(13,HIGH); 
} 
void tres(){ 
digitalWrite(7,HIGH); 
digitalWrite(8,HIGH); 
digitalWrite(9,HIGH); 
digitalWrite(10,HIGH); 
digitalWrite(13,HIGH); 
} 
void cuatro(){ 
digitalWrite(8,HIGH); 
digitalWrite(9,HIGH); 
digitalWrite(12,HIGH); 
digitalWrite(13,HIGH); 
} 
void cinco(){ 
digitalWrite(7,HIGH); 
digitalWrite(9,HIGH); 
digitalWrite(10,HIGH); 
digitalWrite(12,HIGH); 
digitalWrite(13,HIGH); 
} 
void seis(){ 
digitalWrite(7,HIGH); 
digitalWrite(9,HIGH); 
digitalWrite(10,HIGH); 
digitalWrite(11,HIGH); 
digitalWrite(12,HIGH); 
digitalWrite(13,HIGH);

} 
void siete(){ 
digitalWrite(7,HIGH); 
digitalWrite(8,HIGH); 
digitalWrite(9,HIGH);

} 
void ocho(){

digitalWrite(7,HIGH); 
digitalWrite(8,HIGH); 
digitalWrite(9,HIGH); 
digitalWrite(10,HIGH); 
digitalWrite(11,HIGH); 
digitalWrite(12,HIGH); 
digitalWrite(13,HIGH); 
}

void nueve(){

digitalWrite(7,HIGH); 
digitalWrite(8,HIGH); 
digitalWrite(9,HIGH); 
digitalWrite(12,HIGH); 
digitalWrite(13,HIGH);

}
void limpiar(){ 
digitalWrite(7,LOW); 
digitalWrite(8,LOW); 
digitalWrite(9,LOW); 
digitalWrite(10,LOW); 
digitalWrite(11,LOW); 
digitalWrite(12,LOW); 
digitalWrite(13,LOW); 
}

Please guide me through this... I know that you guys are all good at it...