What is the problem and how can I solve it?

Emad el masry, the icon you have circled is described as follows.

Particulate Filter (Diesel Engines)
Filter blocked with soot. See owner's manual.

Which is exactly what the error message on your dash is telling you. Here's a page describing the isssue.

VW Diesel Particulate Filter issues

And by the way, your Malfunction Indicator Light (MIL, AKA "Check Engine") is on as well. You should get the codes scanned to determine the cause, as there's always the potential for serious issues if left unaddressed. If you get a list of the Diagnostic Trouble Codes (DTCs) and add them to your question, we can try and help you figure out what's wrong with your car and get it fixed.

We'll need to know the year and model of your Volkswagen if you want any more help, though.