To update the text displayed on your receipt, navigate to Configurations > Config page > Receipt. From here, you can click into each of the 'Header', 'Body', or 'Footer' drop-downs and update the copy to match your desired wording.
You can further customize receipts so those printed from SellTreez (orders rung up at the point of sale) or Fulfillment (orders from eCommerce) include different information, depending on your needs. Simply select the appropriate section when updating your configurations.