Setting up a grocery mobile app for curbside pickup

Plan on setting up Magento as a simple mobile app for grocery pickup. It will only have ordering feature, no payment processing. Will also need mobile number validation. I dont plan on storing customer profiles, just a list of what they last ordered (which will eventually get overwritten by the next order).

Would appreciate your recommendations on how to get started?

Should i deploy Magento on-premise or should I go PaaS from the get-go?

Thanks