Below will temporarily block the x.x.x.x ip

firewall-cmd --zone=drop --add-source=x.x.x.x

Below will unblock the x.x.x.x ip

firewall-cmd --zone=drop --remove-source=x.x.x.x

Below will list the blocked ip's in the drop zone

firewall-cmd --zone=drop --list-all

Below will add port xxxx permanently as tcp type

firewall-cmd --zone=public --permanent --add-port=xxxx/tcp

Below will block a port. Substitute xxxx for your port number

firewall-cmd --zone=drop --remove-port=xxxx/tcp

Below will block a port permanently. Substitute xxxx for your port number

firewall-cmd --zone=public --remove-port=xxxx/tcp --permanent