As we click on MDIParent form you will see Below or we can use menus as well as ToolStrip task with the help of control as shown Below with the help of an Arrow.

As in the above figure we can see all the functionalities as normal notepad as vertical tiles, Horizontal Tiles, cascade, close all, Arrange Icons etc.

The Code Snippet as shown below

publicpartialclassMDIParent1 : Form
    {
        privateint childFormNumber = 0;//Initializing childformno as 0.
  
        public MDIParent1()
         {
            InitializeComponent();
         }
  
        privatevoid ShowNewForm(object sender, EventArgs e)
         {
            Form childForm = newForm();//Creating Object of Form
            childForm.MdiParent = this;
            childForm.Text = "Window " + childFormNumber++;
            childForm.Show();
         }
  
        privatevoid OpenFile(object sender, EventArgs e)
         {
 //Creating an object of openFileDialog and checking the open file into the same form.
            OpenFileDialog openFileDialog = newOpenFileDialog();
 //openning the file as initial directory            
 openFileDialog.InitialDirectory = Environment.GetFolderPath(Environment.SpecialFolder.Personal);
 openFileDialog.Filter = "Text Files (*.txt)|*.txt|All Files (*.*)|*.*";
            if (openFileDialog.ShowDialog(this) == DialogResult.OK)
            {
                string FileName = openFileDialog.FileName;
            }
         }
  
        privatevoid SaveAsToolStripMenuItem_Click(object sender, EventArgs e)
         { //Creating an object of savefile dialog
            SaveFileDialog saveFileDialog = newSaveFileDialog();
//saving the file in a initial directory            
            saveFileDialog.InitialDirectory = Environment.GetFolderPath(Environment.SpecialFolder.Personal);
            saveFileDialog.Filter = "Text Files (*.txt)|*.txt|All Files (*.*)|*.*";
//Checking condition for save Dialog box
            if (saveFileDialog.ShowDialog(this) == DialogResult.OK)
            {
                string FileName = saveFileDialog.FileName;
            }
         }
  
        privatevoid ExitToolsStripMenuItem_Click(object sender, EventArgs e)
         { //Closing the application
            this.Close();
         }
  
        privatevoid CutToolStripMenuItem_Click(object sender, EventArgs e)
         {
         }
  
        privatevoid CopyToolStripMenuItem_Click(object sender, EventArgs e)
         {
         }
  
        privatevoid PasteToolStripMenuItem_Click(object sender, EventArgs e)
         {
         }
  
      privatevoid ToolBarToolStripMenuItem_Click(object sender, EventArgs e)
         {
            toolStrip.Visible = toolBarToolStripMenuItem.Checked;
         }
  
    privatevoid StatusBarToolStripMenuItem_Click(object sender, EventArgs e)
         {
            statusStrip.Visible = statusBarToolStripMenuItem.Checked;
         }
  
       privatevoid CascadeToolStripMenuItem_Click(object sender,EventArgs e)
         {//for cascading
            LayoutMdi(MdiLayout.Cascade);
         }

 privatevoid TileVerticalToolStripMenuItem_Click(object sender,  EventArgs e)
         {//for Tile verticle
            LayoutMdi(MdiLayout.TileVertical);
         }

  
        privatevoid TileHorizontalToolStripMenuItem_Click(object sender, EventArgs e)
         {//For Horizontal
            LayoutMdi(MdiLayout.TileHorizontal);
         }

        privatevoid ArrangeIconsToolStripMenuItem_Click(object sender, EventArgs e)
         {//for Arrange icons
            LayoutMdi(MdiLayout.ArrangeIcons);
         }

    privatevoid CloseAllToolStripMenuItem_Click(object sender, EventArgs e)
         {
            foreach (Form childForm in MdiChildren)
            {//closing Form
                childForm.Close();
            }
         }
  

The Output of the code is shown as