NOTE: final code with all working circuits

//c1 - defining led/button pins [opportunity, 2but]
#define ledPin 22
#define buttonPin 2
#define buttonPin2 3

//c2 [who is jtr, 3but]
#define ledPin2 24
#define buttonPin3 4
#define buttonPin4 5
#define buttonPin5 6

//c3 [motive, 2but]
#define ledPin3 26
#define buttonPin6 7
#define buttonPin7 8

//c4 [target & victims, 2but]
#define ledPin4 28
#define buttonPin8 9
#define buttonPin9 10

//c5 [killing stop, 3but]
#define ledPin5 30
#define buttonPin10 11
#define buttonPin11 12
#define buttonPin12 13

int C1 = 0;
int C2 = 0;
int C3 = 0;
int C4 = 0;
int C5 = 0;

//c1 - boolean of led/buttonpress
boolean ledState = LOW;
boolean btnPressed = false;
boolean btnPressed2 = false;

//c2
boolean ledState2 = LOW;
boolean btnPressed3 = false;
boolean btnPressed4 = false;
boolean btnPressed5 = false;

//c3
boolean ledState3 = LOW;
boolean btnPressed6 = false;
boolean btnPressed7 = false;

//c4
boolean ledState4 = LOW;
boolean btnPressed8 = false;
boolean btnPressed9 = false;

//c5
boolean ledState5 = LOW;
boolean btnPressed10 = false;
boolean btnPressed11 = false;
boolean btnPressed12 = false;

unsigned long previousMillis = 0;        // will store last time LED was updated
unsigned long previousMillis2 = 0;
unsigned long previousMillis3 = 0;  
unsigned long previousMillis4 = 0;
unsigned long previousMillis5 = 0;  
const long interval = 5000;
const long interval2 = 8000;
const long interval3 = 5000;
const long interval4 = 5000;
const long interval5 = 8000;

void setup() {
  Serial.begin(9600);
//c1 - defining led/button input & output
  pinMode(ledPin, OUTPUT);
  pinMode(buttonPin, INPUT);
  pinMode(buttonPin2, INPUT);
  digitalWrite(ledPin, LOW);

//c2
  pinMode(ledPin2, OUTPUT);
  pinMode(buttonPin3, INPUT);
  pinMode(buttonPin4, INPUT);
  pinMode(buttonPin5, INPUT);
  digitalWrite(ledPin2, LOW);

//c3
  pinMode(ledPin3, OUTPUT);
  pinMode(buttonPin6, INPUT);
  pinMode(buttonPin7, INPUT);
  digitalWrite(ledPin3, LOW);

//c4
  pinMode(ledPin4, OUTPUT);
  pinMode(buttonPin8, INPUT);
  pinMode(buttonPin9, INPUT);
  digitalWrite(ledPin4, LOW);

//c5
  pinMode(ledPin5, OUTPUT);
  pinMode(buttonPin10, INPUT);
  pinMode(buttonPin11, INPUT);
  pinMode(buttonPin12, INPUT);
  digitalWrite(ledPin5, LOW);
  
}

void loop() {
  unsigned long currentMillis = millis();
  unsigned long currentMillis2 = millis();
  unsigned long currentMillis3 = millis();
  unsigned long currentMillis4 = millis();
  unsigned long currentMillis5 = millis();

//c1 - boolean check for button
  boolean btnState = digitalRead(buttonPin);
  boolean btnState2 = digitalRead(buttonPin2);

//c2
  boolean btnState3 = digitalRead(buttonPin3);
  boolean btnState4 = digitalRead(buttonPin4);
  boolean btnState5 = digitalRead(buttonPin5);

//c3
  boolean btnState6 = digitalRead(buttonPin6);
  boolean btnState7 = digitalRead(buttonPin7);

//c4
  boolean btnState8 = digitalRead(buttonPin8);
  boolean btnState9 = digitalRead(buttonPin9);

//c5
  boolean btnState10 = digitalRead(buttonPin10);
  boolean btnState11 = digitalRead(buttonPin11);
  boolean btnState12 = digitalRead(buttonPin12);

 
/* button checker (whether if the button works)
Serial.print(btnState);
Serial.print(",");
Serial.print(btnState2);
Serial.print(",");
Serial.print(btnState3);
Serial.print(",");
Serial.print(btnState4);
Serial.print(",");
Serial.print(btnState5);
Serial.print(",");
Serial.print(btnState6);
Serial.print(",");
Serial.print(btnState7);
Serial.print(",");
Serial.print(btnState8);
Serial.print(",");
Serial.print(btnState9);
Serial.print(",");
Serial.print(btnState10);
Serial.print(",");
Serial.print(btnState11);
Serial.print(",");
Serial.println(btnState12);
delay(100);
*/

// C1 (2 buttons)
if ( btnState == HIGH && btnPressed == LOW ) {
   C1 = C1 + 1;
    btnPressed = true;
  }

  if ( btnState2 == HIGH && btnPressed2 == LOW ) {
   C1 = C1 + 1;
    btnPressed2 = true;
  }
  if(C1 == 2){
    digitalWrite(ledPin, HIGH);  
    }else{
      digitalWrite(ledPin, LOW); 
      // reset to base timer
      if (currentMillis - previousMillis >= interval) {
      previousMillis = currentMillis;  
        C1 = 0;
        btnPressed = false;
        btnPressed2 = false;
      }
     }

    //Serial.println(C1);
    //delay(100);
    
// C2 (3 buttons)
if ( btnState3 == HIGH && btnPressed3 == LOW ) {
   C2 = C2 + 1;
    btnPressed3 = true;
  }

  if ( btnState4 == HIGH && btnPressed4 == LOW ) {
   C2 = C2 + 1;
    btnPressed4 = true;
  }

    if ( btnState5 == HIGH && btnPressed5 == LOW ) {
   C2 = C2 + 1;
    btnPressed5 = true;
  }

  if(C2 == 3){
    digitalWrite(ledPin2, HIGH);  
    }else{
      digitalWrite(ledPin2, LOW); 
      if (currentMillis2 - previousMillis2 >= interval2) {
      previousMillis2 = currentMillis2;  
        C2 = 0;
        btnPressed3 = false;
        btnPressed4 = false;
        btnPressed5 = false;
      }
     }

      //Serial.println(C2);
      //delay(100);

// C3 (2 buttons)
if ( btnState6 == HIGH && btnPressed6 == LOW ) {
   C3 = C3 + 1;
    btnPressed6 = true;
  }

  if ( btnState7 == HIGH && btnPressed7 == LOW ) {
   C3 = C3 + 1;
    btnPressed7 = true;
  }
  if(C3 == 2){
    digitalWrite(ledPin3, HIGH);  
    }else{
      digitalWrite(ledPin3, LOW); 
      // reset to base timer
      if (currentMillis3 - previousMillis3 >= interval3) {
      previousMillis3 = currentMillis3;  
        C3 = 0;
        btnPressed6 = false;
        btnPressed7 = false;
      }
     }

    //Serial.println(C3);
    //delay(100);

// C4 (2 buttons)
if ( btnState8 == HIGH && btnPressed8 == LOW ) {
   C4 = C4 + 1;
    btnPressed8 = true;
  }

  if ( btnState9 == HIGH && btnPressed9 == LOW ) {
   C4 = C4 + 1;
    btnPressed9 = true;
  }
  if(C4 == 2){
    digitalWrite(ledPin4, HIGH);  
    }else{
      digitalWrite(ledPin4, LOW); 
      // reset to base timer
      if (currentMillis4 - previousMillis4 >= interval4) {
      previousMillis4 = currentMillis4;  
        C4 = 0;
        btnPressed8 = false;
        btnPressed9 = false;
      }
     }

    //Serial.println(C4);
    //delay(100);
  
  // C5 (3 buttons)
if ( btnState10 == HIGH && btnPressed10 == LOW ) {
   C5 = C5 + 1;
    btnPressed10 = true;
  }

  if ( btnState11 == HIGH && btnPressed11 == LOW ) {
   C5 = C5 + 1;
    btnPressed11 = true;
  }

    if ( btnState12 == HIGH && btnPressed12 == LOW ) {
   C5 = C5 + 1;
    btnPressed12 = true;
  }

  if(C5 == 3){
    digitalWrite(ledPin5, HIGH);  
    }else{
      digitalWrite(ledPin5, LOW); 
      if (currentMillis5 - previousMillis5 >= interval5) {
      previousMillis5 = currentMillis5;  
        C5 = 0;
        btnPressed10 = false;
        btnPressed11 = false;
        btnPressed12 = false;
      }
     }

      Serial.println(C5);
      delay(100);
}