"Don't know. I'm a little bit confused!! please can you send me the code in c# language. I'm not able to deal with images in a winform. I don't know what to do. it's my first experience."
We're here to help people learn how to program, as well as with application design issues, and to assist people when they are stuck writing code. With rare exceptions, no one here is going to send you the code.
It's important you take the initiative and start writing code. But, if you are not ready for that, the least you can do is search CodeProject for articles that use PictureBox, and ImageList, and that show you how to create thumbnails.
Start by studying the WinForm PictureBox Control. Put a PictureBox on a Form, and write the code to load an Image into it.
Learn how to create a ThumbNail of an Image read from a File.
Put a ListView on a Form, and set its 'View property to 'LargeIcon, or 'SmallIcon.
Put an ImageList Component on the Form, and add Images to it.
Set either the 'LargeImageList or 'SmallImageList properties of the ListView to the ImageList depending on whether you specified the 'View property as 'LargeIcon or 'SmallIcon.
Add Items to the Listview using the ListViewItem constructor that takes a string, and an index into the ImageList to display the Image. YourListView.Items.Add(string, Int32).