DEMOUP/DemoPractick/Main.xaml.cs

using DemoPractick.Model;
using DemoPractick.Pages.Users;
using DemoPractick.VM;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;

namespace DemoPractick
{
    /// <summary>
    /// Логика взаимодействия для MainWindow.xaml
    /// </summary>
    public static class FramePage
    {
        public static Frame page { get; set; }
    }
    public static class Data
    {
        public static Entities Sush { get; } = new Entities();
    }
    public partial class Main : Window
    {
        ViewModel VM = new ViewModel();
        public Main()
        {
            InitializeComponent();
            FramePage.page = MainPage;
            MainPage.Navigate(new Pages.Users.Products(VM));
        }
    }
}