How to invoke a 64-bit app in a 32-bit process space?

Question

Hi, in a 64-bit WinOS ennvironment, how can a 32-bit process/app such as CMD invoke a 64-bit app?

For example, we have a 32-bit launcher (aka installation program). It needs to invoke a 64-bit 3rd party installer. Presently, doing so will render the OS to say it's not a Win32 App.

If you know of any workaround or suggestion, I am all ears...

thanks, CT