if you have friends who have it on steam you can connect to them quite easily using : direct connect
LAN is by definition...local server, so if you don't do it yourself you can't access it.
trying to access random multiplayer games will just result in you being kicked off instantly (been there done that).

global chat server was disabled by larian studios, if i had to guess i'd say it was to prevent a mass amount of insults flying here and there for no reason.

you can create a multiplayer and invite friends in it (you can invite them directly if they are on GoG or they can rejoin you by using direct connect if they are on steam (which is them putting in your ip address so they can access your game, you can find it in option menu if i recall right).

that's about it. you can look around the forum for ppl who also want to start a multiplayer and begin with them.

Thanks for replying
Yet still there should be some online lobbys for all to join, like "all/new players welcome" etc . My problem is that my searchlist is empty. Is it because of GOG version or some firewall problems. Just asking if it should be this way.

the global chat server is normal, it was maybe a feature used in early stages of development.
no regardless of the version you should be able to see the games, when the version is not the same as yours they are greyed and youcan't join.

are you in : story > multiplayer ?
i just tried and i see a whole bunch of games around 40, it's either your firewall messing things up or you're not in the right menu.

Oh well You were right. I was in a wrong menu...
Well I guess it happened because I fought that you start multiplayer through game master mode, and in panic I did not think about it(I bought the game 2 daysago and this was a second time I launched it) . Also everytime i started playing campaign I alwasy clicked singleplayer brainless or i thaught that it's local co-op. Now i feel like an Idiot....
Still thanks for help.

PS If u want to play you cam add me (I'm not that braindead all the time)

no problem
and sure i'll add you right away.

Game master is about creatig your own adventure it seems, i watched a youtube vid made by one of larian dev explaining the whole thing (well, the basics).
if you're into modding and creating your own "plateau" game (with dice rolling and such) yyou should totally go into this mode, to create one you go into : prepare campaign.