I need to add a form to a website

Do you provide a php file to upload to my website's server (GoDaddy) that will allow a form that filled out to be sent to an email address?

The best way to embed your form in GoDaddy website builder is wiht iFrame code. Inside of this guide you can find how to get iFrame code of your form: 

https://www.jotform.com/help/148-Getting-the-Form-iFrame-Code 

All our forms have Email Notification set by default. Email Notification is used to notify you via email, when your users submit your form. 

Explanation of Email Notification and Autoresponder Settings

I also noticed that you have created your form on guest account. I would suggest you to sign up for a free account. You can use this link to signup: https://www.jotform.com/signup 

If you use same email address you used to post this thread, you form will be automatically moved to your free account.

Hope this will help. Let us know if you need further assistance.

I have created a free account and set up a form. It was easier than I thought.
Sent from my iPad
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I am glad to hear that you successfully created free account and that you have embedded your form to your GoDaddy website. 

Feel free to contact us if you have any other questions.