uint16_t uiTestVar = 0xE402; 

enum class permission 
{
  READ,
  WRITE
};

template <typename tVar>
auto bitManipulation (permission p, tVar &input, byte byBitPos, bool x) -> bool;
auto bitRangeCheck(uint8_t uiSize, byte byBitPos) -> bool;

void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);

  // Try to read out of range;
  Serial.println(bitManipulation(permission::READ, uiTestVar, 17, false));

  // reading a in Range bit: 
  Serial.println(bitManipulation(permission::READ, uiTestVar, 7, false));

  // writing a bit:
  bitManipulation(permission::WRITE, uiTestVar, 4, false);
  Serial.println(uiTestVar);

}

void loop() {
  // put your main code here, to run repeatedly:

}

// The counting of the bitpositions is starting with index 0 
template <typename tVar>
auto bitManipulation (permission p, tVar &input, byte byBitPos, bool x ) -> bool
{
  auto size = sizeof(input);
  if(!bitRangeCheck(size, byBitPos))
  {
    Serial.println("Error: Bitposition is out of range!");
    return false; 
  }
  else 
    {
        switch (p)
        {
        case permission::READ : 
        return (input >> byBitPos) & 1UL;
        break;
        
        case permission::WRITE : 
        if (x)
            input |= 1UL << byBitPos; // set bit to 1
        else 
            input &= ~(1UL << byBitPos); // Set Bit to 0
        break;
    
        default: 
        Serial.println("No valid permission option!");
        break;
        }
    }
}
// checking whether the passed bitPosition is out of range of the variable
auto bitRangeCheck(uint8_t uiSize, byte byBitPos) -> bool
{
    switch (uiSize)
    {
    case 1:
        if (byBitPos > 7)
            return false;
        else
            return true;
        break;
    // uint16 or int16
    case 2:
        if (byBitPos > 15)
            return false;
        else
            return true;
        break;
    // uint32 or int32
    case 4:
        if (byBitPos > 31)
            return false;
        else
            return true;
        break;
    // uint64 or int64
    case 8:
        if (byBitPos > 63)
            return false;
        else
            return true;
        break;
        // uint8 or int8

    default:
        Serial.println("This Size is not programmed to check: " + String(uiSize));
        break;
    }
}