Backend script in Nakama [closed]

I got a job in game company that uses Nakama as backend.
My assignment is to write a script, that will take data from open street map, about buildings by ID, that will be send to this script.

The only thing I have is a link for Nakama backend and login&password.

Problem is:

I don’t know how to do that. It wasn’t in the job description.

Question:

Can somebody send me links, that will push me into the right direction or explain how to add scripts to backend if I only have a link for the dashboard?

I tried looking up answer, but I can’t tell that it helped me