rest – What approach is best suited for food ordering?

The scenario is to have a website/server where users can order food. Then this order should somehow be inserted to the restaurant’s local database.

My customer doesn’t want a direct connection between the server and the restaurant’s local db.

So, how am I going to handle the orders? I think there are 3 options here

PS: I think this is a language-agnostic question. But in case it matters, the technologies I’m using are Kotlin, Java, Spring Boot, Hibernate, MySQL