Okay.. Welcome to Linux World!!
The very first thing you should do is
Click==>Application(Left Bottom Corner)==>SyetemTools=>Terminal
type
tell us what distribution to you use..
if you are talking about msn sort of messenger then its AMSN in Linux world, a clone to msn
after knowing you distribution with
If Fedora:
(your root password)
Code:
yum install -y amsn
if Ubuntu:
Code:
sudo apt-get update
Code:
sudo apt-get install amsn
but you should have a pre installed Internet Messenger
placed under: Applications====>Internet===> Messenger
Let us know what else do you feel difficult..
Good Luck!
Cheers!!