It's possible to create a room in LAN to play with my friends without internet ?

no sorry this isn't possible if you want to if you and your friends go on the Internet you can create a room go into lockdown the command is /lockdown and then set a password the command is /passwd [pass here] and to get into the server /password [pass here] or /pass [pass here]



p.s. to set the password the command is acctually /passwd [pass here] I did not make a typo