Thanks for the good explanation!
Frankly, I’m still lost.
It seems that Discourse requires 1-2GB RAM and 10GB of storage volume.
I could easily allocate it with any laptop, considering that only users of the same country would use it for the meantime.
I think that the company has a few servers of its own (instead of AWS S3 or such).
If it’s installed of these servers, that would be great. But just for testing it, I guess that it would be better try it first on a laptop. Do I still need to pay for a domain?