(1) I think you would like to setup an autoresponder. So, users would recieve an email when they submit the form.
1. Click on "Setup and Share" tab,
2. Click on "Add New Email"
3. Select "Autoreponder" and click next,
4. On the right bottom corner, select the email question on your form
5. On the next page enter a text form your autoresponder email
6. Finish and save your form.
(2) To change your Thank You page:
1. Click on "Setup and Share" tab on the form builder toolbar
2. Click on "Thank You"
3. Select "Custom URL" option and enter a URL from your own web site.