The puppet agent is not available in the base repository for the CentOS 7 release.

Puppet 3.6.2 is available in the EPEL repository. This is somewhat painfully old. Puppet 5.5.10 will debut in Debian Buster. The IUS repository does not feature packages for this either.

yum install ruby will give you Ruby by default.

Install in this order; facter; hiera; puppet. It will all go to /usr, for some reason that is a mystery to me.

Test it out:

[amoe@localhost bin]$ puppet --version

Check that we can access our puppet server.

[amoe@localhost bin]$ ping -c 1
PING ( 56(84) bytes of data.
64 bytes from ( icmp_seq=1 ttl=63 time=29.7 ms

--- ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 29.778/29.778/29.778/0.000 ms

Modify your hostname to something sensible, /etc/hostname. Also add an alias to the hostname into /etc/hosts.

Most files will install to /opt/puppetlabs by default.

Also install bind-utils for the host program that is required by Facter.