If you are looking for a country-specific list of IP addresses to block, there is a GitHub project which offers those lists, among other things.
They were previously at a different URL, but seem to have changed since I last worked my iptables script logic.
For example, to obtain the list of IPs recognized as originating from Canada (my own country), the path to IPv4 list is
https://github.com/ipverse/country-ip-blocks/blob/master/country/ca/ipv4-aggregated.txt
Similarly, for IPv6,
https://github.com/ipverse/country-ip-blocks/blob/master/country/ca/ipv6-aggregated.txt
and, lastly, for “aggregated” JSON,
https://github.com/ipverse/country-ip-blocks/blob/master/country/ca/aggregated.json
Similar to the above, but apparently more extensive (comprehensive?) is the set of IP lists offered under the heading of “geo-ip-blocks”.
Those are offered here, with a similar sub-directory structure:
https://github.com/ipverse/geo-ip-blocks