a question here, is there any commitment involved?
or voluntary basis as in free only join in, not free then dont participate also its alright.

Yes, anybody may join. It will be an event-by-event basis, you can join in any event if you are free at the particular time. No obligations to be involved in every event. A few members will be selected for to be in committee for each event, the rest just need to turn up.

IMHO, it should be composed in the first few post. scattering the answers for various questions everywhere makes it diff for ppl who are interested to get the answers to their questions.