Adding a customized page in drupal

I have this page I want to link to my drupal site. The page contains a chatroom I customized. Howev开发者_运维问答er, since I'm still new to drupal, I don't know how to link it.

I tried creating a primary that linked my page to drupal and it did work but when I tried to print (in php) the "$user->name", there came an error since it cannot recognize the variable I was trying to call.

I really need to figure it out.

Error Messages appearing: Notice: Undefined variable: user in ...[directory]

Notice: Trying to get property of non-object in ...[directory]

You are probably missing

global $user;

if you want to print out the logged in users name.