We need to put the checkbox "Send to Messenger" [1] feature in a product page of an e-commerce via Google Tag Manager under the "Buy" button identifying the "#buy-button" div.
When user clicks on the “Add to Cart” button of the e-commerce with the checkbox of "Send to Messenger" selected, and automatically through a Facebook Page we send the product information that the user has interest.
The information about the product like “Title”, “Description” and “Image” of e-commerce can be search through the ElasticSearch API.
Explanatory video
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[1] About the Send to Messenger feature:
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