How to add more currencies to shop

I understand your confusion because there we can find a lot of settings related to currency. Because of this it is better to import localization pack. Go to localization > localization, you will see "import a localization pack" form. From first dropdown select your country (or country with currency you want to add). Then in "content to import" select "currencies" only., then click on "import' button.

your new currency will be added after download (several seconds) and all setting fields will be filled out with proper datas :-)