The quick answer is yes, but it depends on the online casino and the type of prepaid card you use. Prepaid card providers and online casinos have different regulations regarding the payment methods they allow.

With a prepaid card, you cannot borrow money. (It does not function like a credit card.) You only have access to the funds loaded on the card, which can be reloaded, but you cannot utilize more money than you have. As such, prepaid cards do not build credit.