In the theme editor (Customize) Default product > Click Frequently Bought
From your Shopify admin, go to Settings -> Custom data
Click Products β Add Definition.
Please enter the correct Namespace and Key as we noted below.
From your Shopify admin, go to Products -> All products.
Find and choose the product that you want to edit.
In the Metafields, please insert content for "Frequently Bought Together" field.