How do I find out my card balance

No it's a card machine over by the entrance in the game room

Any ride operator or the kiosk

You can also go to their website and at the bottom is a link to register your card and then it will show you the balance.

They have machines where you can add money check the balance and it prints receipts

Ask the front desk

Any ride operator may be able to tell you remaining balance, I gues, if not front desk for sure