Add VitualHost on Debian Problem

Hello, It's driving my self crazy. I've been trying to add a VirtualHost on my Apache2 Debian, but it not working. I did everything as they say : Add a file in sites-available, a2ensite xxxx, apache restart, but no use. So I'm looking for someone who can fix it in few minutes, I need the project done within an hour. I give you a login and password, you connect with SSH, fix the problem and explain to me what I was doing wrong. Thanks