How to response Steam?

Hello Guys

I need help.

I send a ticket to the steam support because of a problem.

Now they responded to may problem and they need mor einformation. but how to i respond to them ? The Email it came from is a noreply email. Please can someone help me on this one. When i click on the message in the email where they need the informations they send me to a website and thats it. where should i put those informations ??

Thanks.