Hey @Yamini, follow these steps to install chef on ubuntu:
Update repositories
$ sudo apt-get update
Change your hostname
$ hostname 'chef.yourdomain.com'
set up NTP
$ apt install ntp
$ systemctl start ntp
$ systemctl enable ntp
$ ntpq -p
Download and install chef
$ wget https://packages.chef.io/files/stable/chef-server/12.15.8/ubuntu/16.04/chef-server-core_12.15.8-1_amd64.deb
$ dpkg -i chef-server-*.deb
Configure chef
$ chef-server-ctl reconfigure
Check chef status
$ chef-server-ctl status
Install web-management console
$ chef-server-ctl install chef-manage
$ chef-server-ctl reconfigure
$ chef-manage-ctl reconfigure
$ chef-manage-ctl reconfigure --accept-license
Create a directory for holding all the keys
$ mkdir ~/.chef
Create new admin by executing the following command
$ chef-server-ctl user-create admin Chef Administrator chef@yourdomain.com StrongPassword -f ~/.chef/admin.pem
Create a new organization using the following command
$ chef-server-ctl org-create my_org 'My Organization' --association_user admin -f ~/.chef/my_org.pem
Access web-console
http://Your-Server-IP