How To Play Commandos Behind Enemy Lines On Windows 10 -

// graphics.cpp
#include <d3d9.h>
HRESULT initD3D(HWND hWnd) 
    // Initialize Direct3D
    IDirect3D9* pD3D = Direct3DCreate9(D3D_SDK_VERSION);
    // ...

If you do not already own the game, buying it on Steam is the most straightforward option. The Steam version has been slightly updated to run on modern systems, though it still requires one specific tweak.

@echo off
setlocal
cd /d "%~dp0"
start /wait "" " Commandos.exe" // Compatibility mode for Windows XP (SP2)