Stage Comitee - how does that work?

Hello there,
the other day I was reading stuff at www.stagecommittee.org so I wanted to ask how those things listed there work (language course, sports etc.). Will there be some official intro to these activities and this "body" when we get to Brussels? I just don't want to be late with subscriptions to certain activities.

You will not be late, it will be explained once you arrive, no worries! And there are plenty of great activities, it is definitely a great idea to participate in as many as possible!