My servers at home are Ubuntu 20.04.   I configured their Uncomplicated Firewall, UFW.   UFW does work with IPv4 and IPv6.   I have a Uncomplicated Firewall complete section on my  other server under Linux.   You will see I add the entire delegated prefix.    I could list all of them separately.

To start before you enable UFW, YOU MUST CONFIGURE SSH.

sudo ufw allow from to any port ssh
sudo ufw allow from 2600:1702:980:25ef:0:0:0:0/64 to any port ssh