WooPOS can only accept single currency price listing but for payment we accept multi-currency (If you would like to set up currency for payment you can follow the link here: Payment Type Setup)
(Recommended) Currency symbols and format should be set up in the Windows Control Panel.
(Not Recommended) There is another way if you cannot find settings in the Windows Control Panel. You can use the store attribute to overwrite this setting. Add an attribute called “Currency Symbol” in the store entity. And then put your Currency Symbol in store settings.