Hello,
To do the same please follow the steps.

Sub domain is part of the domain, it’s like subletting a room of an apartment.

A records has to be setup on the dns.

For example :

mydomain.com has IP 1.1.1.1.0 and hosted with some other company.

Now to get the sub domain

anothersite.mydomain.com

of which the site is actually on another server then to create a sub domain

Login to your domain manager

And go to dns manager and add an A record in domain manager like this

anothersite.mydomain.com and point the IP to the other server 127.0.0.1

And that’s it.

Wait for the DNS propogation usually happens instantly give it a time to reflect and point the sub domain name anothersite.mydomain.com and you are all set to go now as your sub domain points to Digital Ocean.

What is the impact of having a CNAME of * with this.

I’ve configured irc.mydomain.org to point to my droplet but no DNS queries will return that box. I set this up over 2 days ago.