With changes Facebook has made to Facebook Conversion Tracking we have updated the way it works in your console and how you can use to segment your audience and target your customer or like type customers with a range of Ads Facebook has to offer.
Shop > Shop Settings > Options > Shop Settings > Shop Options > Facebook Tracking ID > Paste in code > Save
The tracking ID can be found within the Tracking Pixel code supplied to you from Facebook. You will just need to insert the 16 characters found in the code in the brackets. See image below for an example.
Follow Facebooks guide on how to generate the Facbeook Pixel here
Follow here to see what it tracks here