how can i create an MDI application in VB.NET?

Open a new Windows Application in Visual Basic .NET. The application will open with a default form, Form1. Add another form, Form2 to this application by right-clicking on the project name in Solution Explorer window and selecting Add->Add Windows Form. You can add some controls to Form2. For this application we will make From1 as the MDI parent window and Form2 as MDI child window. MDI child forms are important for MDI Applications as users interact mostly through child forms. Select Form1 and in it's Properties Window under the Windows Style section, set the property IsMdiContainer to True. Setting it to true designates this form as an MDI container for the child windows. Once you set that property to true the form changes it's color. Now, from the toolbox drag a MainMenu component onto Form1. We will display child windows when a menu item is clicked. Name the top-level menu item to File with submenu items as New Child Window, Arrange Child Windows and Exit.