You can add a Facebook pixel ID to the preferences of your online store in Shopify admin to integrate the pixel with your online store. Using this integration doesn't require you to edit your online store code. 1. From your Shopify admin, go to Online Store > Preferences
In the Facebook Pixel section, add your Facebook pixel ID. If you're adding a pixel for the first time, then enter the Facebook pixel ID. If you're changing to a new Facebook pixel from an existing one, then click Change before entering the new Facebook pixel ID.