i would like to know something

Question

Hi every Body iam new C# developer to that great site with great background about C# i thank everybody here for continous knowledge they offer here so i need to develop A program with timer after specific time it logs off windows the same as log off code in microsoft windows when you click the following start > log off > then you will see three buttons appear in borderless form then don't press any button just you will see the desktop is becoming deactivated and become like just image you can't press any thing on your desktop except when you click cancel button i want to do something like that with C# is there any help about that please please refer to me at [email protected]