Magento 2 Guest to Customer - Cynoinfotech
https://www.cynoinfotech.com/product/guest-to-customer-magento-2-extension/
Magento 2 Guest to Customer functionality refers to the process of converting a guest customer into a registered customer within the Magento 2 e-commerce platform. By converting a guest customer to a registered customer, the individual gains additional benefits and features associated with having an account. Magento 2 guest customer is someone who completes a purchase on a website without creating an account. They provide their necessary information during the checkout process, such as their name, email address, and shipping details, but they do not create a user account.