When you get off the plane, as you walk with the other passengers, before descending to Immigration, there should be people asking if you are international transit (transito internaçional). Just show the boarding pass for your next flight. They'll direct you where to go. You won't likely be alone.

I think the limit is something like 8-10 hours, after which you'd need to have a visa and wouldn't be considered transit. You can confirm things with your airline. Your first airline will check for visas, so be sure they are clear on you being able to transit or they won't let you on the plane. Make sure your bags will be transferred (i.e., the two airlines have an interline agreement for the transfer of bags, which is normally the case).

Options for good or drink are pretty poor within the airport's secure areas.