You can add a contact form by using the button on text editor (as in the image below) or by typing the shortcode (as in the example here below).
You must select one of the contact forms you have created on Forte admin panel → Contact forms → Create your forms (watch the video tutorial… it is from another theme, but it is the same). After creating a form you must some fields to it. To edit a form you must go to Forte admin panel → Contact forms → The name of the form.
You can also put a form into a sidebar by using the widget available on Forte.