You want to display a message text box on the checkout page of your store. The message text-box will be used to collect any extra information from the user at the time of placing an order. For example, a customer wants to get the delivery of the product between 2 pm-6 pm. So, he/she can provide this information in the text box at the time of checkout.
You can add a message text-box on the checkout page of your store to collect the user input. To do so, you are required to create an Order Option form containing the message field.
Follow the below-mentioned steps to create the Order Option form: