The message that you took a screenshot of tells you the exact problem:
Your server's hostname is 18.104.22.168, which is apparently the server's main IP address. That is not a valid hostname.
The exact message was: The hostname must be a Fully Qualified Domain Name! (22.214.171.124)!
(Incidentally, it is usually easier to copy and paste text in a terminal program, instead of taking a screenshot. PuTTY automatically copies text to the clipboard if you just drag the cursor to select some text.)
A valid hostname has three parts: host, domain, top-level domain. Here is an example fictitious hostname:
In my example:
- myserver = host
- mybigdomain = domain
- com = top-level domain (or TLD or tld)
The hostname cannot be just a domain name, so mybigdomain.com would not be a valid hostname. Also, the hostname cannot start with www, so /www.mybigdomain.com would not be valid.
What most administrators do is take the main domain they will use for hosting, and add a unique identifier in front of it. Many use host or server, but you can use anything you want, as long as it is not www.
You need to change the hostname on your server. Once you have given the server a valid fully-qualified hostname as I have just described, run /usr/local/cpanel/cpkeyclt again to activate the license.