Credit card is written as 信用卡 in Chinese. It is pronounced as xìn yòng kǎ.

Unfortunately, many credit cards issued outside China can not be used inside China. So if it is better to check if you can use your credit cards before make an order. You can ask 我可以用这个信用卡吗 (wǒ kě yǐ yòng zhè gè xìn yòng kǎ ma )？meaning 'may I use this credit card?'

我可以用xxx吗? (wǒ kě yǐ yòng xxx ma )？is a useful phrase to ask ask permission if you can use something.
If the answer is 可以 (kě yǐ), it means 'yes, you can'.
If the answer is 不可以(bú kě yǐ), it means 'no, you can't'.