Header Name (key) not being recognized when trying to create connection

It’s entirely possible that I’m misunderstanding how to connect my api key, but I’m using the Google Civic Information API and I believe the Header Name is simply ‘key’. I realize that most other APIs use api_key or x-rapidapi-key, or some variation of that. Unfortunately, it doesn’t appear that I can create a connection with the Header Name set to ‘key’. When I try, the ‘Create Connection’ button remains unclickable.

Here is an example of the url I use to make a get request:

When creating the Kor connection, does the following seem correct?

Name: Google Civic Info
Header Name: key
API URL: googleapis.com/civicinfo/v2
Domain 1: jmg0343.github.io/elections    (I'm trying to use github pages)

Am I missing something? Perhaps I need to add ‘key=’, but that doesn’t seem right.