This should help …
By far one of the best explanations of the Cart concept I have seen on the forum by the great @Jeff_Hager …
I think the App can be copied also so be patient and go through the post and look under the hood. You might have to make some changes and customised it for your use case (Restaurant) but in the main, you should be okay, if you are patient to learn firstly. All the best with your venture…
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