GET Request not working for REST API

I installed the restAPI plugin and I am admittedly new to APIs, but I can’t get this to work:


I substituted my server name in, and changed the port to match admin port. I chose the option to use a secret key and added “&APIID={MYSECRETKEY}” to the string. I can’t seem to get a response in the browser, and I get a 404 error when I try to use it in a web page after receiving admin login prompt page. Can someone please open my eyes here? I can’t figure out where I’m going wrong. For reference, this is my final URL that I am trying to use with the GET request: