Also nearly everyone is using docker for Lemmy and as long as unraid lets you run docker commands you should be fine.
Docker compose is (now) part of docker. It's a way to describe all the containers you want, and then docker goes and does it. You should 100% learn docker compose, and Lemmy already has a compose file in their repo. So you should be able to copy paste and say docker compose up -d
But it's only a 2 core, 4gb ram, and I think a 100mbit line, though I have yet to test the network throughput to its maximum.
We average about checks 15-25% CPU usage at the moment over the past 24 hours.
We are using Cloudflare Infront of our server to help with spikes, but honestly it doesn't do much except for serving the images.
This is due to the fact that lemmyui interacts via websockets and all federation are pretty much POSTs.
Lemmy itself is very CPU and memory efficient. The biggest problems all other instances are having are database related and the inefficient nature that some of the queries are.
In the long run, I would like to get a dedicated colo instance for the database server, which would give us enough growing room for up to 10k+ users even with the current database inefficiencies, but until we get about $200-250 per month in recurring monthly donations there will no way we can get to that.