Magento 2 Out of Stock Notification allows store owners to send alert notifications if the product is in stock for which they had subscribed. Also, it will enable store owner to view the list of customers who are interested in the notification for out of stock products.
You can check how to configure Meetanshi's Magento 2 Out of Stock Notification extension.
The extension is a feature-pack both for the customers and admin. Improve the user experience of your store with Magento 2 Out of Stock Notification module. Make it easy for customers with updates about the stock status of their favorite items in your Magento 2 store.
Learn the stepwise configuration of the Magento 2 Out of Stock Notification extension at https://meetanshi.com/blog/magento-2-out-of-stock-notification-meetanshi/