There are two areas to head to for correct setup, within your theme settings.
Firstly, your Shopify admin settings must have a default store currency selected. This will be displayed at the checkout and is outside of the theme's control.
Here's a guide to provide further information on how to do this:
Secondly, to set your theme to display different currencies on your storefront, head to:
- Online store > themes > customise
- General settings > currency
- Add your required default currency in the way of three capital letters such as "CAD" to "default currency".
- Add any other currencies you would like to display in the drop-down on your store, within the "Supported Currencies" box:
'Supported currencies' are the "list" that customers will be able to choose from. "Default currency" is the currency that will show on your storefront if no other option from the list is selected. Remember, your theme controls these two components on your storefront, but the Shopify platform controls the overall "store currency" mentioned above which will display at checkout.
Lastly, remember to switch this feature on!