Installation via Quickstart isn't working

Installed Python 3,10
Installed Instapy

-> When running the basic Quickstart it first opens in Firefox? Shouldn't this be Chrome by default?
Second, it is able to log in, but following after it directly goes to the link: https://www.instagram.com/'username' and then Firefox tells me it cannot find the page. Anybody know how to tackle?

The code is exactly the same as downloaded exept with my login credentials.