ASP.NET Core App - Web Service - Architecture Guidance

Question

We have a plan to implement a web app using ASP.NET Core MVC/SQL Server(using ADO.NET) and host in MS Azure Platform.

Our client wants to have web service feature to implement all CRUD operations for this web app, since client might not deploy the database on Azure and would prefer regular deployment to PROD environment. However, the web app and service are being planned to host in Azure - IIS.

 

1. When we plan to keep all data access logic in web service, what would be the best option for this scenario? Going for WCF Service or Web API?
2. What would be the best solution architecture for both web app and service? (e.g. case1: A service method would return an object of a custom class and this class definition should be understood by the receiving web app).
3. Do we need to keep the service project within the same solution of ASP.NET Core web app project or separate it to a different solution?

Experts, could you please provider your suggestions?