Problems With Variable Data

#include <iostream>

using namespace std;

int Option;
bool Exit = false;
char Input[10];
char P;

void BookingMainMenu(); //Booking Main Menu Function

void BookingSportsCar(); //Sports Car Booking Function

void Booking4x4(); //4x4 Booking Function

void BookingVan(); //Van Booking Function

class AllCars{
      public:
             int TotalMilesDriven;
             int TankFillingAccumulation;
             int NumberOfRepairs;
             int TaxRate;
             char InsuranceGroup[1];
             int TyreChangeCount;
             int DateBookedOut;
             int NumberOfDaysBooked;
             char FuelType[6];
             char CarRegistration[7];
             char FuelTankSize[4];
             char MainFuelCapacity[4];
             int NumberOfSeats;

             float MilesPerGallon();
             int RepairsPerMile();
             float AveMilesUsed();

             AllCars(int totalmilesdriven, int tankfillingaccumulation, int numberofrepairs, int taxrate, char insurancegroup[1], int tyrechangecount, int datebookedout, int numberofdaysbooked, char fueltype[6], char carregistration[7], char fueltanksize[4], char mainfuelcapacity[4], int numberofseats ){
                   TotalMilesDriven = totalmilesdriven;
                   TankFillingAccumulation = tankfillingaccumulation;
                   NumberOfRepairs = numberofrepairs;
                   TaxRate = taxrate;
                   InsuranceGroup[1] = insurancegroup[1];
                   TyreChangeCount = tyrechangecount;
                   DateBookedOut = datebookedout;
                   NumberOfDaysBooked = numberofdaysbooked;
                   FuelType[6] = fueltype[6];
                   CarRegistration[7] = carregistration[7];
                   FuelTankSize[4] = fueltanksize[4];
                   MainFuelCapacity[4] = mainfuelcapacity[4];
                   NumberOfSeats = numberofseats;
             }

             };



class SportsCars{
      public:
             bool SoftTop;
             bool Alloys;
             };

class FourByFour{
      public:
             bool OffRoad;
             bool TowingHitch;
             };

class Vans{
      public:
             bool HighTop;
             };

int main(){
    system ("cls");
    cout << "!================== Welcome To Matt's Auto's ==================!" << endl;
    cout << "\n";
    cout << "!========== Please Select The Option You Wish To Use ==========!" << endl;
    cout << "\n";
    cout << "1) Book A Vehicle" << endl << "2) View Our Vehicles" << endl << "3) Exit" << endl;
    cout << "\n";
    cin >> Option;

    while(!Exit){

    switch(Option){
                   case 1:{
                        BookingMainMenu();
                        break;
                        }
                   case 2:{

                        break;
                        }
                   case 3:{
                        Exit = true;
                        break;
                        }
                   default:{

                   }
                   }
    }

    return 0;
}

void BookingMainMenu(){
     system ("cls");
     cout << "!======================== Book A Car ==========================!" << endl;
     cout << "\n";
     cout << "!========== Please Select From The Following Options ==========!" << endl;
     cout << "\n";
     cout << "1) Book A Sports Car" << endl << "2) Book A 4x4" << endl << "3) Book A Van" << endl;
     cin >> Option;
     system("PAUSE");

     if (Option == 1){
          BookingSportsCar();
          }
     else if (Option == 2){
          Booking4x4();
          }
     else if (Option == 3){
          BookingVan();
          }
     }

    // AllCars car;

void BookingSportsCar(){
     system ("cls");
     cout << "!==================== Sports Car Booking Form ====================!" << endl;
     cout << "\n";
     cout << "!============= Please Answer The Following Questions =============!" << endl;
     cout << "\n";
     cout << "What Fuel Type Would You Like?" << endl;
     cout << "\n";
     cout << "1) Petrol" << endl << "2) Diesel" << endl;
     cin >> Input[0];
        if (Input[0] == 1){
            AllCars.FuelType == "Petrol";
        }