You can add a Facebook Pixel event directly to your forms and calendars. This pixel will then fire upon a submission of the form or calendar. This is a default event that registers with Facebook as 'Submit Application' for a Form Submission and 'Schedule' for a Calendar Submission
What you'll need:
Your Facebook Pixel ID
Step 1: Form Pixel
Navigate to the Form Builder.
Select Your Form.
Click Options > Input your Pixel ID into the Pixel Section.
Integrate Form and Save.
Step 2: Calendar Pixel
Navigate to Settings > Calendar.
Click in to edit the Calendar (Pencil Icon)
Input the Pixel ID into the Calendar.