i think because its a demo they dont have a actual storyline yet more like a sort of roam the two areas and collect stuff to build or enhance(?) or you can let yourself be F***ed by the enemies if you wish. Theres a area you can go to just to view the enemies doing so to you
Sorry that there are no story / tutorial in the game so far. However there is a help page that you can find it by pressing ESC to open menu. There will be some tips for you about how to play the game.