Temporary checkout list without user login

Hi to everyone, I am trying to build a restaurant menu and I want users to add an item to a checkout page but instead of using stripe/buy button, the order list will just be added to google sheets and the waiter will check the updated gsheets on their end to process the order.

Can I do this without the user logging in? I tried add row but I failed. I am assuming I’ll need a unique ID then the items that are added (or maybe favorited) in a gsheet, uniquely for the customer.

please advice

How would you know which customer is ordering, what is the unique identifier here?