I doesn't sound to me like you mean multiplayer, but if you do: No. This game is for one player only.
It sounds more like you are trying to play the same copy on more than one computer at the same time. This is also something you cannot do. Each copy of this game can only be registered to one Steam account. Each player must have their own seperate copy on their own seperate Steam account.
You must buy another copy and register it to a second Steam account or take turns.
...I think. Steam has an offline mode, but I don't know if it makes what you want possible.