2 weeks, Rio, alone, what to do? any associations? (Rio de Janeiro)

Hello,

I am French (Girl), I live in Germany and I will have a 2 weeks break beginning of October in Rio de Janeiro.
I will come alone to relax and would like to enjoy what Rio de Janeiro has.

While I am here, I would like to meet people too, and even thought the time is short, I thought that being involved in an association would help. The type of association (sportive, cultural, project) does not matter as long as there are friendly people:) of course I will be a volunteer.

* If you could tell me any association names to which I could enrol / help, that would be great !!

* I would be happy to have also any tips from you, about places where I should go / visit and anything that I must do :)

* If you want as well to go for some drinks & visit Rio with me, I am in too :)

Wouah :) you have read the message up to this point, ^^
Thanks for taking the time to do it and if so, for your comments

Saï XD