how do i create extra functions in a form button

I need a form integration but to act like a landing page.

You enter your information, press a download button at bottom of form send email. and name / details gets emailed to us while they get their file.

Is this something that can be achieved?

To let users download files:

You can follow the steps provided in this guide to add a downloadable file to your form: How-to-Add-a-Downloadable-File-to-Your-Form

As an alternative, you can also set up an autoresponder email that will send them a file. Here is a guide on how to configure this: How-to-Attach-a-File-to-Autoresponder-Emails

To add various fields:

You can add different fields to your form as per your requirement form the form elements.

To get details on email:

You can set up an email notification that will send you all the details on your email address once the user submits the form. Here is how to configure the same: Setting-up-Email-Notifications

Let me know if you have any questions.