convert an app that is already working well from a restaurant app into a kiosk app

convert an app that is already working well from a restaurant app to a kiosk app, I have an application that was created for restaurants and it has everything you need to order online restaurants, I want to copy it and convert it into a kiosk type application so that work locally in restaurants and create several functionalities such as creating bigger buttons, a new check out in utorized.net, creating a functionality so that the new Kiosk has the ability to print locally in the restaurant through printer lan