Preparing your system
Open the terminal and run the following command
sudo apt-get install perl libnet-ssleay-perl openssl libauthen-pam-perl libpam-runtime libio-pty-perl apt-show-versions python
Now you need to dpwnload webmin deb package using the following command
wget http://prdownloads.sourceforge.net/webadmin/webmin_1.580_all.deb
Install downloaded package using the following command
sudo dpkg -i webmin_1.580_all.deb
This will install webmin now you need to access https://ubuntu-serverip:10000