Yeh, exactly.
And the “dynamic DNS” part handles your public IP address changing with 0 pain.
You either buy a domain (like example.com), or there are free domain name providers that give you a subdomain (like mycooldomain.example.com) of one of their domains.
You then run an additional service on your home server that checks what the current public IP address is. If it changes, it notifies the DNS responsible for your domain/subdomain, which then points to your new public IP.
To connect to your VPN, you only ever care about “mycooldomain.example.com” and never the underlying IP address.

…
As long as your ISP isn’t running CG-NAT of course 😵‍💫