Thank you for your suggestions everyone. I was able to create a second Discourse using a combination of these two websites:
- Running other websites on the same machine as Discourse (@angus 's response was especially helpful)
- How to install Multiple discourse on one server | by Pushpender singh | Medium
Although these two websites suggest a very similar process, the second website acts as a more beginner-friendly supplement to the first link and I strongly recommend for anyone who attempts to do the same thing to read both while setting up their system.
Right now, my second Discourse is currently marked as “insecure” (because I copied the certificate from the previous instance in /var/discourse/shared/standalone/ssl in order to avoid the “file not found” error when I tried sudo nginx -t). Could someone tell me how to make the second Discourse site https secure (the first one has no issues)? Thank you in advance.