How to make or join a town

Hello everyone, for example a hermit or two guys that live together want to make a town, what they need to know about recruiting new ppl? Are you expected to have a brickwall at your home and let the others live outside and interact with them and overtime when you can trust them let them in?
How a town is supposed to be and what should be the roles of citizens? What biomes are preferable?
I only was in one when server started and we random ppl joined and searched together for a place, then we settled, each build a p claim then someone made a town and overall there was not much interaction only when we were cutting some trees or making coal clamps and slowly everyone left or were afk, then again back then you could have all the skills in 2-3 days.
To my understanding if all are new characters over time you can see with what ppl you are playing, but if you want to join a town, what you should expect? What if you want to start in Popham or when new expedition is out?
How a town is supposed to be and what should be the roles of citizens? What biomes are preferable?
I only was in one when server started and we random ppl joined and searched together for a place, then we settled, each build a p claim then someone made a town and overall there was not much interaction only when we were cutting some trees or making coal clamps and slowly everyone left or were afk, then again back then you could have all the skills in 2-3 days.
To my understanding if all are new characters over time you can see with what ppl you are playing, but if you want to join a town, what you should expect? What if you want to start in Popham or when new expedition is out?