I’m trying to figure out how to integrate a third party software that I’m using for inventory into wix using the API key. I have generated a key and a secret just need to figure out where to put it on the site backend.
You will need to read about how to access 3rd party services in the article Corvid: How to Access 3rd-Party Services with the Fetch API .
Take a look at the Advanced examples , many of them access 3rd party services. A couple of good examples to start with are: Example: Using the Places API from Google Maps services and Example: Send email with the SendGrid REST interface .