Doha bank’s prepaid card is called Click card, I have one, charge is QR50 for 1 year, and it works as a visa card while shopping online. I have a Doha bank account so I am recharging it online from my account, it take one working day for the money to be present in card once you request to transfer money from account to the card. Alternatively, I think (I never tried), you can charge it in any of Doha bank branches, .
I heard IBQ also has one like this.

As far as I know, you can’t charge just voip with that as they do not have credit card purchase option, if some1 know how to charge just voip by credit card pls let me know.