Jetpack JSON API configure button not showing [closed]

You don’t need to configure anything. As soon as you connect Jetpack to your account and activate the JSON API module, you’ll be able to to use the API. You can double check that by running some test queries using the REST API Console here. You could also just try to load one of the endpoints in your browser, like so.

If you’re still having issues working with Jetpack’s REST API, I’d suggest contacting the Jetpack support team through this form, or in the Jetpack support forums. As mentioned in on-topic, it’s best to use appropriate support channels for third party plugins and themes.