If you want the user login in your game with Facebook native c3 plugin see this. Demo. All My tutorials here. Fisrt of all , when the user logged in you can get...
I don't got the second part, what url I need to paste in Valid OAuth Redirect URIs?
If you are testing in preview mode on PC use the link : preview.construct.net/local/index.html
if you are using on a website put the link there . GianniB