Software Serial Bluetooth RC Car

#include <SoftwareSerial.h>
SoftwareSerial BTSerial (11, 12);
// BTSerial (Rx, Tx); Based on the Aduno board
// Connect the pin of 11 pin of Arduino board to TX pin of Bluetooth module, connect Pin 12 and RX
#define EN1 3 // Motor A to motor driver A-1A pin connection
#define EN2 4 // Motor A to Motor Driver A-1B Pin Connection
#define EN3 6 // motor B and motor driver B-1A pin connection
#define EN4 7 // motor B and motor driver b-1B pin connection
int carSpeed = 200; // Speed of RC car
void setup () {
BTSerial.begin (9600); // Communication with Bluetooth module via software serial communication
// Initialize both pins of motor A to output mode
pinMode (EN1, OUTPUT);
pinMode (EN2, OUTPUT);
// Initialize both pins of motor B to output mode
pinMode (EN3, OUTPUT);
pinMode (EN4, OUTPUT);
}
void loop () {
if (BTSerial.available ()) {
  char command = BTSerial.read (); // Save command received in Bluetooth to command
  if (command == 'F' || command == 'f') {
    // function call to advance RC car when receiving F or f as input
    moving_forward ();
  }
  else if (command == 'B' || command == 'b') {
    // function call to reverse RC car when receiving B or b as input
    moving_backward ();
  }
  else if (command == 'L' || command == 'l') {
    // function call that rotates RC car left when receiving L or l as input
    moving_left ();
  }
  else if (command == 'R' || command == 'r') {
    // function call that rotates RC car right when receiving R or r as input
    moving_right ();
  }
  else if (command == 'S' || command == 's') {
    // Function call to stop RC car when receiving S or s as input
    stop_moving ();
  }
  else {
    // Function call to stop RC car when not recognizing command
    stop_moving ();
  }
}
// Time delay
delay (100);
}
void moving_forward () {
// Rotate motor A forward
digitalWrite (EN1, HIGH);
digitalWrite (EN2, LOW);
// Rotate motor B forward
digitalWrite (EN3, HIGH);
digitalWrite (EN4, LOW);
}
void moving_backward () {
// Rotate motor A in the reverse direction
digitalWrite (EN1, LOW);
digitalWrite (EN2, HIGH);
// Rotate motor B in the reverse direction
digitalWrite (EN3, LOW);
digitalWrite (EN4, HIGH);
}
void moving_left () {
// Rotate motor A forward
digitalWrite (EN1, HIGH);
digitalWrite (EN2, LOW);
// Rotate motor B in the reverse direction
digitalWrite (EN3, LOW);
digitalWrite (EN4, HIGH);
}
void moving_right () {
// Rotate motor A in the reverse direction
digitalWrite (EN1, LOW);
digitalWrite (EN2, HIGH);
// Rotate motor B forward
digitalWrite (EN3, HIGH);
digitalWrite (EN4, LOW);
}
void stop_moving () {
digitalWrite (EN1, LOW);
digitalWrite (EN2, LOW);
digitalWrite (EN3, LOW);
digitalWrite (EN4, LOW);
}