Ligend,
In the Social configuration area, there should be tabs for "K2 Comments" and "K2 Like". In that area, you can configure how the social widgets are added to K2 categories and items.
If you're not seeing those tabs, it means that JFBConnect isn't detecting that K2 is installed. If you think that's the case, please check your installation of K2 and then let us know what tabs you do see in the Social area, as that will help narrow down what JFBConnect 'thinks' is installed.
Thanks,
Alex