If you yet is not able to understand a proposed layering pattern, just don’t use it. No use simply putting N layers if you don’t understand why each one exists.
There is a concept KISS (Keep it simple, stupid), I’m not calling anyone stupid, it’s the concept. Translating is keep it simple. Watch this lecture from a Stackoverlflow contributor, it’s in English. You’ll see the simplicity behind this site. Simplicity often meets.
In most cases the simple MVC standard that comes by default in an ASP.NET solution will meet. In your case of an API, you won’t get the Views, but you wouldn’t have to go out creating layers unless it’s extremely necessary, and if you can’t identify if it’s necessary, then don’t.
Focus on delivering the functionality to the customer in a safe and well-done way, at least following the basic principles of object orientation such as separation of responsibility and the DRY.
Take this layer pattern, and try to develop something for testing, so you can learn and understand, but don’t do something that will be sold or put into production with something you don’t master.
The correct answer is that a project does not necessarily represent a layer. Based on this statement no one will know how to give an answer without knowing exactly the code of each project
– Bruno Costa
Hello! Can you tell what is the original intention of each project created?
– Dherik
@Dherik, where I was studying, got a little confused, because all the projects were doing the same thing. I was just calling another project to call another... so I thought it was unnecessary
– Diego Zanardo