Installing Webmin on CentOS or Redhat is extremely easy using yum. Yum also allows you to keep Webmin update to date extremely easy (yum update)
Open the file webmin.repo from the below path, I used vi editor you can use your favourable editor.
vi /etc/yum.repos.d/webmin.repo
Copy and Paste the following text, Save & Exit the file
[Webmin]
name=Webmin Distribution Neutral
#baseurl=http://download.webmin.com/download/yum
mirrorlist=http://download.webmin.com/download/yum/mirrorlist
enabled=1
Install the GPG key.
wget http://www.webmin.com/jcameron-key.asc
Run this command.
rpm –import jcameron-key.asc
Install the webmin now
yum install webmin
Once Webmin has finished installing you should can load the following address in your browser. http://youripaddress:10000
Make sure to open the port 10000 in FIREWALL to access the webmin from your computer.