Type of Form - Submit Button or eSignature?

Hello,

I created a form so our customers can request financing.  It must have a legally binding esignature, preferably submitted via button.

It seems this isn't possible?  I have to use the "this doc requires signatures" when creating the form?  And if that is the case then I do not have the option for the button, nor for field functionality (ex:  Currency).

Thanks!