Hi,
You need to investigate ASP.NET, PhP, Servlets (Java), CGI-Scripting or a web development framework such as Django or Ruby-on-Rails.
Once you have found out about one of thoes then you should be able to see what you need to do.
If your server is Windows based then I would look at ASP.NET, if it is Unix based then I would look into PhP or Servlets (Java).
Justin