For desktop meeting apps like Zoom or Discord, you don't. When you press Start, TranslateMe detects your running meeting app (or lets you pick it in the Inbound tab) and points its microphone at the right virtual audio cable automatically — and its speaker too, when Inbound Translation is on. When you press Stop, your previous audio setup is restored. If the app has a specific microphone or speaker picked in its own settings, set those back to the system default so TranslateMe can route it.
For meetings running in a browser (like Google Meet in Chrome), or if TranslateMe tells you automatic routing isn't available on your PC, set the devices yourself — see How do I route meeting audio manually?.