How to add a contact form

How to build and add a contact form in your page

The Live Composer doesn't contain any contact form module by default. You can use any contact form plugin what display data using shortcodes. For instance, you can try one of the following plugins:

For the following instructions will be used like an example the Ninja Form plugin.

Go to WP Admin > Forms > All Forms and copy the shortcode of the new created form.
Go to your contact page and activate the Live Composer. 
Drag and drop an "HTML module".
Paste the contact form shortcode.
Publish the changes.