Facebook Pixel can be used to monitor your conversions and obtain information about your user provide. The Facebook Pixel ID is a code that can be included in your Landing Pages. The option to add this information can be found both within the Builder as well as in the Dashboard.
NOTE - This is a page-level setting. i.e You can have one Facebook Pixel ID for your landing pages and this cannot be changed for each of the Variants for that landing page.
In the builder - Navigate to Global Settings Panel > Tracking Codes and click on the Tracking IDs Tab.
In the Dashboard - Navigate to the tab Settings > Tracking Codes > Facebook Pixel ID
NOTE - Follow the link to know How to create a Facebook Pixel ID