Sending newsletters to the customers is the best practice to leverage to increase the engagement with the customers. The store owner can send newsletters regarding latest updates, promotions, discounts and so on.
Thankfully, the default Magento 2 allows the send newsletters to customers. For that, you need to configure Magento 2 newsletter from the admin panel.
Visit: https://meetanshi.com/blog/configure-magento-2-newsletter/