gistfile1.cs

public interface IQuery<out T>
{
    T Execute(IDataContext dataContext);
}

public interface IQueryHandler
{
    T Handle<T>(IQuery<T> query);
}

public class QueryHandler : IQueryHandler
{
    private readonly IDataContext dataContext;

    public QueryHandler(IDataContext dataContext)
    {
        this.dataContext = dataContext;
    }

    public T Handle<T>(IQuery<T> query)
    {
        return query.Execute(dataContext);
    }
}

public class CountPeopleQuery : IQuery<int>
{
    public int Execute(IDataContext dataContext)
    {
        return dataContext.People.Count();
    }
}

public class TestController : Controller
{
    private readonly IQueryHandler queryHandler;
    
    public TestController(IQueryHandler queryHandler)
    {
        this.queryHandler = queryHandler;
    }
    
    public ActionResult Index()
    {
        ViewBag.PeopleCount = amountOfPeople = queryHandler.Handle(new CountPeopleQuery());
        return View();
    }
}