Right now there is no blueprint functionality to connect to facebook from blueprints. You can connect to steam and use most of it’s interfaces and create your own verification system (if you really want to) but that’s about it.
You will have to do that yourself in c++.
Cheers
Hellow gyuz! Now i need 2 connect my app to the Facebook and idk how to do it from the Blueprint interface. Pls get some docs about the objects that can connect app and Facebook.
I can resolve your problem! I’ve just released plugin with Facebook implementation for iOS & Android! 
More info:
Patryk,
gameDNA studio