How to test Dynamic DNS created in FreeBSD?

I am learning Unix Networking and have learned to create a DNS server in FreeBSD.
I then wanted to update the entries in DNS zones dynamically so I followed this procedure,

Using this procedure, I can add entries to DNS zones using nsupdate command. But I want to be able to update the DNS zone dynamically, so I installed and setup the DHCP server. I have also added the required keys and other permission in dhcpd.conf file. and have also enabled dhcpd in rc.conf file.

I have started the DHCP server, and it start running, but I am stuck here. I don't know what to do now to make sure that DDNS is working.

Can someone please help me with that ?