"Api-Key" and "Api-Username" for try.discourse.org?

[Lilly]

have you read the api documentation?

especially this

User API keys specification

Discourse contains a system for generating API keys per user if a very specific protocol is followed. This feature facilitates “application” access to Discourse instances without needing to involve moderators. High level description At a high level: Client (desktop app, browser plugin, mobile app) generates a private/public key pair and return url Client redirects to a route on discourse giving discourse its public key Discourse gets approval from user to use app Discourse generat…

also these

Discourse REST API Documentation

Discourse API Please view the Discourse API Documentation site for detailed info: https://docs.discourse.org Deprecation Warning! On April 6th, 2020 we dropped support for all non-HTTP header based authentication (excluding some rss, mail-receiver, and ics routes). This means that API requests that have an api_key and api_username in the query params or in the HTTP body of the request will soon stop working. Please see the example cURL request below for how to update your API requ…