From your other thread that is now closed:
This is just the hostname of your Digital Ocean droplet (i.e. server’s name), so it’s not related to the name of your forum. If you want to change that, the cleanest way is just to deploy a new server and specify a different hostname to Digital Ocean on creation. It can be changed after deployment as well though.
Navigate to discourse folder:
Check/update your configuration:
Then rebuild with the new config:
./launcher rebuild app
If using Cloudflare, make sure to add the Cloudflare template to the app.yml (just to make sure your IP logging is for real IPs, not Cloudflare ips). The section is at the top of the app.yml.
+1 for the advice above of setting up using the official instructions.