Adding Form to your website.

You can add Online form by clicking on Form Menu -> Drag and Drop the block to your site.

Adding more Field by current on the form section and click Form menu again, it will show a Field tab which you can drag and drop a new field to your form.

Form Design 

You can adjust the size, change the color of text and form background by clicking on Design.

Set up email submission received.

Clicking on Email Setup and selecting on send to admin. You can adjust the subject of the email submission and recipient email.

Also, you can set up an email which will be sent to a user who submits the form by checking box send to user and set up for the subject, sender email, sender name and reply to email. 

See How to set the email template for every email sent out to your visitors and admin.