My APP requires a free API key for testing.

I have an app I'm releasing on the Play store the app renders a image with Nano Banana, Lite or Pro. The testers need to get a free API key from AI Studio, I plan to hire a testing service. I have written instructions for the testers they're in my dropbox. I've never released an app before. My question is how do I get the instructions in my dropbox to the paid testers or tesing company I will hire?