You can change the currency of your store by going to Shopify Settings --> General:
Scroll to the bottom and select the desired currency from the drop down under Store currency:
However, please note that all the prices in your Supliful account will be displayed in US dollars (USD), and your card will be charged in USD. Therefore, if your added card is in any other currency, there might be additional charges due to the bank's currency exchange rates.
Please contact your card-issuing bank to get more details on their exchange rates and service fees.