Koha connection to Power BI

From what I understand about Power BI and getting data through a website is to insert the web url into the web portion of 'get data' and it will send a get request to the site and pull data from which you can select what data (if multiple options available) and how it is displayed (transform data).

My issue is that I am trying to get data from a web api called "Koha" within this api I am in need of reports stored by a library to which I am creating a dashboard for my senior project. I include the url in the advanced tab of the web portion of the get data. I then, under the HTTP, include 'username' and 'password' on the left and my credentials on the right. When I submit, it shows the login screen of the koha website and the html code to follow.

Right now I just cannot get the credentials part down so that when the request is sent from power bi to koha, the login process goes through with the provided credentials on power bi, then loads the data from the url provided.

Please let me know if you need more (reasonable) information or need to clarification on anything. This is my first time asking for help (waited a few months to ask) so please let me know.

Thank you for your time!

Applications and other sources used:

Power BI Desktop

Koha (open-source integrated library system)