Template – To / From / Message fields
We use the built in WooCommerce template system so that you can fully customize these fields.
To override the HTML for these fields, copy this file:
To here (create any missing subfolders):
Once the file is in your theme folder, open it up in a text editor and make any changes.
You can find out more about customization here: https://docs.woocommerce.com/document/configuring-woocommerce-settings/#section-21