Maybe you have this sorted out already. If not, can you confirm that you are following this guide for installing Discourse: discourse/docs/INSTALL-cloud.md at main · discourse/discourse · GitHub? Also, make sure your server’s hardware and software meet the requirements that are outlined here: discourse/docs/INSTALL.md at main · discourse/discourse · GitHub.
I’m not the best person to answer your questions. In the past, after following the guide with a fresh Ubuntu 22.04 server, the setup has just worked for me without any additional configuration.
If you’re still having problems, someone from the community can probably help.