Yes, it is very difficult to configure Discourse to work with Plesk. You need to understand a lot about Discourse, Docker, and Plesk. I’ve done it before, but Plesk regularly broke the configuration since you’re essentially working against what it’s designed to do.
I’d start with Discourse on its own server to see how that works and then try to get it to work with Plesk if that’s something that you think will be lots of fun.
AI won’t be much help since you’re trying to do stuff that’s pretty much not documented at all.
Then why are you asking?
I can probably do it, but it would take me 1-5 hours at $300/hour. We’d likely both be unhappy with the process.