What's the easy way to integrate a payment method into my form?

I don't have the option that you explained in your response.  Do I need to create a payment widget or how can I implement a payment from my product?

I checked one of your forms: https://www.jotform.com/build/72706195603154

And you have Purchase order integrated there:

I'm not sure if you have any difficulty in adding the payment field?

You can just drag and drop it from the Payments tab.

Also, please be mindful that you can not add more than one payment field to one form.

Let us know if you have any further questions.

Thank you!