How to add the submit button?

I created a form however I do not know how to add the submit button. Are we able to accept a deposit? I cannot change payment method from purchase o

The Submit button is a basic form field. Simply drag & drop it to the bottom of your form. 

You are using a Purchase Order Payment field. You can collect payments with any other payment field. 

Mastering Payment Form Integrations with JotForm

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