C++ HELP for window32

[catcat]

LRESULT CALLBACK window_callback(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
return DefWindowProc(hwnd, uMsg, wParam, lParam);
}

int WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdline, int nShowCmd)
{
WNDCLASS wc;
wc.style = CS_HREDRAW | CS_VREDRAW;
wc.lpfnWndProc = window_callback;
wc.lpszClassName = "Window";
}

By the way IM using Visual Studio 2019[/img]