In case you are not using any firewall, you should be able to reach your machine. As suggested by ash_zz_00 could you check what your public IP is and then try telnet etc.

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Prasanta

Just a thought: Sometimes it takes hours or even days for domain registrars to propagate changes through the Internet. Your domain name may not resolve if it has been activated recently or if your dynamic DNS provider was configured very recently. If that is the case, it may just be a matter of time. You could try pointing your web browser to your public IP, on port 80 (XXX.XXX.XXX.XXX:80) then see what you get.

If none of the former is the case, try pinging your domain from the outside. Does it resolve? Do you get a response? If it doesn't resolve, try pinging your public IP. If you get pings back from your host, then there is probably something misconfigured in your Apache settings.

is that dangerous to tell us the real domain you have, maybe from this give
us advantages to scan and trace the issue

The IP is public... I can ssh and VNC into the host externally.

I'm at a loss at this point.. any other suggestions? TIA!