Follow this instructions for creating a new Textbox
Open the Textbox App for Shopify:
The App Dashboard will shop up. To create a new text field, click on the green button on the right top corner.
Define a unique name for your Textbox. You can later change the name and all settings at any time.
Click on the „save“ button for creating your first Textbox.
You have created now a new Textbox and you can check if the Textbox is appearing on your products on the storefront.