Sending Auto Reply When User Submits From Contact Form

Hello
I am trying to generate an auto reply sent to a user’s email when a they inquire about a reservation using our contact form. The contact form on this particular page was a “drag and drop” form. It was not custom generated.

I am trying to implement the instructions on this page.

The problem I am running into is not being able to connect the form to any kind of data set. I can click on other elements on the page and it gives me the option to connect it to a dataset.

Is it possible to connect the existing form fields to a dataset, or do I have to create a new form from scratch?

The form is on this page.
https://www.othellos.us/copy-of-edmond

Thank you