How to alter the API request to purge the cache of one or more URLs

Worked like a charm. I used an ID generated by the verification API request instead of the Zone ID. Stupid mistake.

Also, how to alter the API request to purge the cache of one or more URLs instead of the whole site?

Since the reply in another discussion was split into a separate topic, here is the URL for the comment I was replying to.

Answered by @df1228