Advice on starting a BBS?

I am making a retro club at school, although I already plan to start printing newsletters for the club,for a bit of fun, i want to make a buletin board system for us lads with computers.

I've got a unlimited data plan for my internet, and i hear that running it on a raspberry PI would maybe be a good idea. (Although i love old computers, i dont trust one to be running nonstop in my room without coming across an issue.)

I'm not familiar with BBSes yet, but with your help, i could learn a thing or two.

Please share your wisdom and advice on starting one!

Thanks so much in advance!