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Field on screenshot you provided is Configurable list widget. If you want to set up Configurable list widget on your form, this guide can help you:
In case that you want to sell book I would suggest you to add payment field to your form. Inside of this articles you can find out more about payment tools and how to set payment form:
If I did not understood your question correctly, please explain in more details what you are trying to achieve. Also provide us ID of the form you are working on.
Hope this will help. Let us know if you need further assistance.