Hello @LizL7 ,
This already exists via WooCommerce integrating with Wordpress. You'd setup WooCommerce for your ecommerce elements, and integrate that into your Wordpress site. Then, you'll connect your WooCommerce setup with your Constant Contact account.
For guidance on setting up your WooCommerce and integrating it with Wordpress, I'd advise checking their support resources.
See also:
Create an automated abandoned cart email for your Shopify or WooCommerce customers
Guide: WooCommerce and Constant Contact
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