If your delivery app is simple enough you may be able to use an out-of-the-box delivery app solution. But your unique delivery marketplace will need custom business logic. Your business logic is what makes everything work in the background. Often, this means you should start from scratch using a tested, enterprise delivery platform.
If you are providing delivery for many independent stores or restaurants, you will need robust multi-vendor capabilities. Each vendor needs to be able to easily handle orders and their products and menus. And you, as the administrator, need to be able to manage all the vendors.
You also need to efficiently manage your drivers. You can do traditional dispatching, or let drivers pick orders nearby. And the delivery drivers will also need their own app. This lets them claim deliveries, handle orders and payments, and mark orders as complete on the go.