The good thing is you have options when it comes to printing out barcodes for your products. We actually have a guide here on our retail barcode labels app that includes information on how to get it setup, along with valuable information on the supported label types (sizes), and printer settings.
If there is anything else I can help you with, please let me know.
Dirk | Social Care @ Shopify - Was my reply helpful? Click Like to let me know! - Was your question answered? Mark it as an Accepted Solution - To learn more visit the Shopify Help Center or the Shopify Blog