What you want is a static website with all the menus on it.
Just a dumb HTML page would already be enough.
You bill them for data entry, they give you their delivery menu.
You type the entire menu into your webpage. One under the other.
Then you charge them 20 euro per month minimum fee. The restaurants are sorted (by hand) every month by how much they've paid.
The fee has to be that small to force all restaurants to participate.
The question to ask is what you can do for the customer. Bringing all the menu cards together in the same format adds value.
You don't even need a search engine.
First upgrade agenda point for automation would be a restaurant login so that they can save money by doing the menu data entry themselves.
edit:
The guy cant code, all the value will have to come from him promoting the website.
I read below you want to make a food delivery app. If we are actually talking about restaurant delivery and not illicit drugs -- you need the delivery people to have an app that sends you their location, a routing algorithm to choose the closest person to send, logins, payment processing, etc. etc.
Its a major major undertaking that would cost at least $10m if done from scratch.
<unpopular opinion> Building the community is the hardest most important part. If you can find enough people to submit and buy things it becomes worth a visit for the rest of the audience. If they are reasonably competent you can do that with a blog engine or forum software.
When it gets worth building a custom website you might have some issues migrating.
If you have all kinds of special features in mind the 50/50 deal is a good choice.
Therefore, what is the form of the marketplace you can deliver now to validate your idea? In other words: can it be a spread-sheet, Facebook group, online directory, Telegram space, etc... that take the tech out of the equation and that help you create the "marketplace", and then you can port that into your preferred form, informed by the knowledge you acquire running the proto-marketplace?
