To add customer, order, variant, and product metafields, follow these steps:


1. Click "Add Field" and search for the metafields you want to add.

 

2. Add the necessary "metafields" fields.



3. Enter the namespace and key in the provided field. 


For example: "namespace.key" (as in the sample of the image below)



How to obtain the namespace and key?

Obtain the namespace and key from Shopify admin under Settings > Custom Data > Metafield, then define the metafield in the specific store section.