On Cobalt Strike how do I point a domain (in this case a subdomain) to the IP address to create a listener?
Do you mean you have a listener running on your cobalt strike server and want your payload to connect to it via a domain name? In that case you need to modify your DNS record to point to the IP address. Go to your domain name registrar (where you bought the domain) and add an "A" record which ties your subdomain to that IP address. If you Google it your registrar will almost certainly have instructions on how to do it.