newbie question

[Bonny]

The nearest thing to an overview are the old faction previews. Not all unit's who are in the game are included and some may have changed over the time.

https://forums.totalwar.org/vb/showthread.php?t=51037

edit: I would recommend to read TA's thread, too (it explains the recruitment system)
https://forums.totalwar.org/vb/showthread.php?t=74103