Where can I find Facebook app "scheme"

[mkhalila]

Hey I'm using this library alongside react-native-firebase to implement Facebook login for my app. I have managed to locate the app id and client token but I can't find where on the dev console to find the scheme

Thanks in advance.

Also if someone could confirm - do I need to "publish" the app to make authentication work? As there are some details such as privacy policies and data deletion url's etc which I haven't implemented yet