@MotoX80 the problem is not that complicated to understand
This is part of my Windows server 2016:
IP 20.0.0.80 <-- is my intranet IP address and the hostname is obama.local (I don't have a certificate or a website on obama.local, Port 80 is not open to the internet)
IP 170.165.123.93 <-- is my external IP address and and has a certificate for website https://www.obama.com I have port 443 open to the internet
The internet can access https://www.obama.com without any problems
If I try to access www.obama.com or https://170.165.123.93:443 in the intranet I get an error: ERR_CONNECTION_RESET (This is the problem that I need to fix)
@ CandyLuo-MSFT told me "DNS entries just used to resolve domain name to an IP address. First make sure you can access the website by IP address in the LAN. If you are not able to access the website by IP, then this issue is not related with DNS resolution."
I need to resolve the LAN before I work with DNS.
Your suggestion of having 2 certificates. One assign to IP 170.165.123.93:443 and the other certificate assign to IP 20.0.0.80:80 may work?