The short answer would be: https://api.playfab.com/documentation/server/method/AddUserVirtualCurrency. There's also a Client API version available, if you want to turn that on, but I'd advise against that. Making the client authoritative about VC is a guarantee that players will cheat. So the general answer is that you'd use server-authoritative logic to process the answers and reward the VC. If the player can only do a few of these per minute, you could potentially process this via Cloud Script, but you may want to consider using a custom game server, if you want to have tighter control over the experience.
sorry for folow up question ,, but how can i update the UI/ Text without restarting the app?
We don't interfere in the display layer of your game in any way, so how you want to display the information to the player is entirely up to you.
my problem now is i need to stop and play again to update the text. tnx!
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