Request simple source of an ASP.NET MVC

Quote:

i only find about controller and view and model.

You should read about the definition of MVC because I feel like you don't know that the MVC are initials of "Model View Controler"
Model–view–controller - Wikipedia[^]

MVC is an application design paradigm; and as such is language/code agnostic. It is more about Seperation of Concerns than it is about specific code.
MVC5 is just one specific flavor of it, centered on ASP.NET for the code.

Now, back to your question at hand; how to talk to the database.
As you have worked with both WebForms and WinForms then you should have a pretty good idea that there are a few different ways of connecting with a datasource. Some of the older methods are using the dataset designer and good old fashioned ADO. Over the last decasde MS has come out with LinqToSql and more recently Entity Framework.

Most of the tutorials that are out there for building MVC from scratch uses Entity Framework (EF) as the abstract between your Model and the database. What is nice about it is that you can build the DB from your Models in a Code First setup, or you can create the Models from an existing DB in the other setup. EF can even synch a change from your code back to the DB if you add a field or two to the Model.

As for me, all of my CRUD functions/methods are for all practicality done using ADO within my Model.
When I need to migrate web-forms, I have often just brought in the AppData folder (for all the XML data definitions) into a bare MVC app and then defined the CRUD functions to use the imported dataset methods

Tutorialspoint has lots of tutorials and some even have "live demo" environments: ASP.NET MVC Tutorial - Tutorialspoint[^]
it is a bit dated though, they are mentioning Visual Studio 2012.
The database chapter discusses Entity Framework which might be overkill for a simple application.
Here are some alternative lightweight databases: best-databases-for-a-small-net-application[^]