How do u make trainer?

void MW2Kills()
{
    EnableDebugPriv(); //Enables debug privileges so you can write data to memory address
    HWND hWndTarget = FindWindow( NULL, "Modern Warfare 2"); //Looks for window with given title


      if(hWndTarget == 0){
    MessageBox(0, "Cannot find window.", "Error", MB_OK|MB_ICONERROR); //If null show error
  } 


  else {
     DWORD dwProcessId;
     GetWindowThreadProcessId(hWndTarget, &dwProcessId); //Gets process id of specified window and outputs return to dwProcessId
     HANDLE hProcess = OpenProcess(PROCESS_ALL_ACCESS, FALSE, dwProcessId); //Opens process with all access
    if(!hProcess){
      MessageBox(0, "Could not open the process!", "Error!", MB_OK|MB_ICONERROR); //If OpenProcess fails show error
    } 
    else {
    char * p; //Char pointer because of the x
    p = (char*)0x00000000; //Memory address here
     int newdata = 1337; //Changes MW2 kills to 1337
      if(WriteProcessMemory(hProcess, p, &newdata, sizeof(newdata), NULL)){
        MessageBox(NULL, "WriteProcessMemory worked.", "Success", MB_OK + MB_ICONINFORMATION); //If memory write was successful show success box
      } 
      else {
        MessageBox(NULL, "Cannot WriteProcessMemory!", "Error", MB_OK + MB_ICONERROR); //If memory write failed show error box
      }
      CloseHandle(hProcess); //Close handle
      }
    }
}

char * p; //Char pointer because of the x
    p = (char*)0x00000000; //Memory address here
     int newdata = 1337; //Changes MW2 kills to 1337
      if(WriteProcessMemory(hProcess, p, &newdata, sizeof(newdata), NULL)){
        MessageBox(NULL, "WriteProcessMemory worked.", "Success", MB_OK + MB_ICONINFORMATION); //If memory write was successful show success box
      }

     int newdata = 1337; //Changes MW2 kills to 1337
      if(WriteProcessMemory(hProcess, (LPVOID)0x00000000, &newdata, sizeof(newdata),  NULL)){
        MessageBox(NULL, "WriteProcessMemory worked.", "Success", MB_OK +  MB_ICONINFORMATION); //If memory write was successful show success box
      }

/* VisualCustomKick Function "EnableDebugPriv" (Date 09.04.2008)
    This function enables you to access the Modern Warfare 2 process
    Note: You have to be logged on on an administrator account
    Courtesy of Listing
    http://visualcustomkick.com/forums/index.php?PHPSESSID=25bbd05938190ecf656407dcbb688e8a&action=profile;u=1
    */

void EnableDebugPriv()
{
    HANDLE hToken;
    LUID sedebugnameValue;
    TOKEN_PRIVILEGES tkp;

    if ( ! OpenProcessToken( GetCurrentProcess(),
        TOKEN_ADJUST_PRIVILEGES | TOKEN_QUERY, &hToken ) )
        return;
    if ( ! LookupPrivilegeValue( NULL, SE_DEBUG_NAME, &sedebugnameValue ) ){
        CloseHandle( hToken );
        return;
    }
    tkp.PrivilegeCount = 1;
    tkp.Privileges[0].Luid = sedebugnameValue;
    tkp.Privileges[0].Attributes = SE_PRIVILEGE_ENABLED;
    if ( ! AdjustTokenPrivileges( hToken, FALSE, &tkp, sizeof tkp, NULL, NULL ) )
        CloseHandle( hToken );
}