If you’re running in Proxmox, it isn’t a bad idea to have Discourse in its own LXC container for simplicity with managing ports and resources. That’s what I do and what the majority of people do when using cloud compute.
Discourse does not come with any proxy for your host system. If you aren’t able to open port 80/443 on your network (either if you dont want to or if your ISP blocks it), you should look into Cloudflare Tunnels or something else like ngrok