The Stardew Valley Casino offers the same gambling options as any real casino.
In the top left corner of the room, you can check your statistics that will be displayed in a terminal. You can use Qi coins for gambling, as well as in order to purchase items. There is an exchange machine to the right from Qi - you can use it to exchange gold to Qi coins, the exchange rate is 10:1.
To access it, you have to complete “The Mysterious Qi” quest: otherwise, the Bouncer won’t let you in. You can access the Casino through the back door of Oasis, in the Calico Desert.
