In Magento, delivery date and time can be added as an option for customers to select during the checkout process. This can be achieved through the use of a Magento extension or custom code. The extension or custom code can provide a calendar or drop-down menu for customers to select the delivery date and time, which can then be stored as part of the order information. The delivery date and time can also be displayed on the order confirmation page and in the customer’s account for easy reference.