Hello Lord  Mormont , do you have already builded the  Altar of Mara ?  Without that one you can't capture a craftsman's hamlet like the message of the game said there...

I started playing 2 days ago. This task is impossible to complete..

well  you  still have  more  time  if  you follow  the game  prompts your Altar will appear  as a quest get  clicking Mate :)

You will not be ablet o build it until you research Barbarians

Yeah some of the quests can't be completed by very new players.  Don't worry though this won't be a problem for long, you should get that stuff unlocked pretty quickly if you play actively.