This is a bit sloppy because the tabs are all messed up so it may not have everything on the right line, but I think this is what you want.

Code:
#include <cstdlib> 
#include <iostream> 

using namespace std; 

int main() 
{
    int input = 0;
    int y; 
    int x; 
    double a; 
    double b;
    while ( input == 0 ) {
    cout << "Selection:\n"; 
    cout << "1. Start\n"; 
    cout << "2. LoL\n"; 
    cout << "3. Quit\n"; 
    cout << "Please make your selection: "; 
    cin >> y;
switch (y) { 
  case 1: 
       cout << "***NOTE*** Only actions with 2 numbers total is supported. Format will be a + b; a - b; a / b; a * b;\n"; 
       cout << "Selection:\n"; 
       cout << "1. Addition\n"; 
       cout << "2. Substraction\n"; 
       cout << "3. Division\n"; 
       cout << "4. Multiplication\n"; 
       cout << "Please choose your action: "; 
       cin >> x; 
       switch (x) { 
              case 1: 
                   cout << "Please enter your first number: "; 
                   cin >> a; 
                   cout << "Please enter your second number: "; 
                   cin >> b; 
                   cout << "\n"; 
                   cout << a + b << "\n";
                   break; 
              case 2: 
                   cout << "Please enter your first number: "; 
                   cin >> a; 
                   cout << "Please enter your second number: "; 
                   cin >> b; 
                   cout << "\n"; 
                   cout << a - b << "\n"; 
                   break; 
              case 3: 
                   cout << "Please enter your first number: "; 
                   cin >> a; 
                   cout << "Please enter your second number: "; 
                   cin >> b; 
                   cout << "\n"; 
                   cout << a / b << "\n"; 
                   break; 
              case 4: 
                   cout << "Please enter your first number: "; 
                   cin >> a; 
                   cout << "Please enter your second number: "; 
                   cin >> b; 
                   cout << "\n"; 
                   cout << a * b << "\n"; 
                   break; 
              default: 
                   cout << "Invalid input!\n"; 
                   break; 
                   } 
                    
    break; 
  case 2: 
    cout << "\nWrong Button! =)\n\n"; 
    break; 
  case 3: 
    return 0;
    input = 1;
    break; 
  default: 
    cout << "\nInvalid input!\n\n"; 
  } 
  }
    system("PAUSE"); 
}