MainWindow.xaml

<Window x:Class="Test_MVVM.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:Test_MVVM"
		xmlns:Duc="clr-namespace:ViewModel;assembly=ViewModel"
        mc:Ignorable="d"
        Title="MainWindow" Height="450" Width="800">
	<Window.DataContext>
		<Duc:DIENVIENVIEWMODEL></Duc:DIENVIENVIEWMODEL>
	</Window.DataContext>
    <StackPanel>
		<ListView x:Name="lv1" ItemsSource="{Binding Listdienvien}">
			<ListView.View>
				<GridView>
					<GridViewColumn Header="Mã diễn viên">
						<GridViewColumn.CellTemplate>
							<DataTemplate>
								<TextBlock Text="{Binding ID}"></TextBlock>
							</DataTemplate>
						</GridViewColumn.CellTemplate>
					</GridViewColumn>
					<GridViewColumn Header="Tên diễn viên">
						<GridViewColumn.CellTemplate>
							<DataTemplate>
								<TextBlock Text="{Binding TEN}"></TextBlock>
							</DataTemplate>
						</GridViewColumn.CellTemplate>
					</GridViewColumn>
				</GridView>
			</ListView.View>
		</ListView>
		<TextBlock></TextBlock>
		<StackPanel>
			<TextBlock Text="Mã diễn viên"></TextBlock>
			<TextBox Text="{Binding SelectedValue.ID, ElementName=lv1,Mode=OneWay}"></TextBox>
			<TextBlock Text="Tên diễn viên"></TextBlock>
			<TextBox Text="{Binding SelectedValue.TEN, ElementName=lv1,Mode=OneWay}"></TextBox>
		</StackPanel>
		<StackPanel Orientation="Horizontal">
			<Button Content="Xóa" Command="{Binding DeleteCommand}" CommandParameter="{Binding SelectedValue,ElementName=lv1}"></Button>
		</StackPanel>
    </StackPanel>
</Window>

DataProvider.cs (trong Project Model)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Model
{
    public class DataProvider
    {
        private static DataProvider instance;
        public static DataProvider Instance
        {
            get { if (instance == null) instance = new DataProvider(); return DataProvider.instance; }
            private set { DataProvider.instance = value; }
        }
        public DataClasses1DataContext Data { get; set; }
        private DataProvider()
        {
            Data = new DataClasses1DataContext();
        }
    }
}

DIENVIENVIEWMODEL.cs (trong project ViewModel)

using Model;
using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Input;

namespace ViewModel
{
    public class DIENVIENVIEWMODEL
    {
        ObservableCollection<DIENVVIEN> listdienvien;
        public ObservableCollection<DIENVVIEN> Listdienvien { get => listdienvien; set => listdienvien = value; }
        public DIENVIENVIEWMODEL()
        {
            Listdienvien = new ObservableCollection<DIENVVIEN>(DataProvider.Instance.Data.DIENVVIENs);
            DeleteCommand = new RelayCommand<object>((p) => p != null, (p) =>
              {
                  Listdienvien.Remove(p as DIENVVIEN);
                  //DataProvider.Instance.Data.DIENVVIENs.DeleteOnSubmit(Listdienvien);
                  //DataProvider.Instance.Data.SubmitChanges();
                  //MessageBox.Show("Xóa thành công");
              });
        }
        public ICommand DeleteCommand { get; set; }
    }
}

mấy này nên có code nha! chứ hỏi thế này cũng ko biết đâu mà hỗ trợ

Thì delete thôi. Bạn phải đưa code của bạn lên mới biết bạn sai chỗ nào chứ.

Thì delete thôi, ban đang vướng cụ thể chỗ nào?