What is the problem you are getting? Does it show "unable to connect" on browser or you are facing any permission related problem?
Did you extract the xampp directory in /opt of CentOS?
When you start the LAMPP using command line
Code:
sudo /opt/lampp/lampp start
Have you seen the output carefully?
Is there any error like "Another web demon is already running".
You haven't provided enough information. Paste the output of above command as well as show what browser says when you open
http://localhost in it.