Now I want to this thing by Using thread and I donot know how to use the Thread?
You will have to start by reading the docs.
Then if you have specific questions, feel free to ask.

But I am not sure a thread is a good solution to your problem.
If the only thing you want to acheave is to have the GUI responsive while waiting for some operation to finish, you can just show a progress bar.
This way the user will konw that the application has not hang up, and he will know in which state of progrees the operation is.
A thread makes sense only when you want to allow the user to do something else while this operation is taking place.