I was able to register without stating that I work or live in Vienna.
After registering you will receive a QR code that can be used to pick up the test kits at any of the pickup/drop off locations like Billa or Bipa.
The results are in both English and German. Included in the results there is a document/ID number that I believe can be your passport number.
To take the at-home test you can use the same login that you used to register or sign in as a guest. This means that if someone else registers and picks up a test, you should be able to use it for yourself with all your own personal details (if for some reason you were not able to register).
Hope that helps
Credit:stackoverflow.com‘