SECONDS — as soon as you complete the payment, the domain is registered automatically.
However, you won't be able to see the domain active until a few hours later, since the new domain's data needs to propagate across the internet. Generally all domains are working within a couple of hours after payment.
Keep in mind that if it's your first time ordering from Bacan, the registration process may take a little longer, as it is necessary to carry out some security and anti-fraud checks on new customers to prevent the fraud that is so common on the internet.