This short video will show you how to correct the error:
This error is actually cased by not having firewalld installed on your system.
In this video you will see how to install firewalld
To fix this issue you need to run the following commands:
sudo yum install firewalld sudo
systemctl start firewalld sudo systemctl
enable firewalld sudo systemctl status firewalld
Once these commands are run you can then start using firewall-cmd command.