How to save game in iOS using GameCenter?

I was trying to implement save game feature in my game. My game is in both Android & iOS.
For Android I’m using GooglePlayGames to save & load user’s progress in clouds.
But for iOS GooglePlayGames is deprecated.

I checked this link, & came to know that iOS GameCenter also supports save game feature almost like GooglePlayGames. But I’m not getting any well tutorial or guide for that.

Is there anyone using GameCenter for save game? Please help.

More than one year later and I am facing the same issue as @dnaskar , has anyone managed to find anything on this topic?