Thanks for the additional info. I'd not heard of Divinopolis, so that is interesting in itself. First, about flights. If they aren't already booked, I'd consider flying into or out of another city than Rio--say Salvador if you want to explore the culture of the northeast or Manaus for visiting the Amazon. Consider open jaw flights--into one airport out of another. There are international flights to Belo Horizonte, the nearest major airport to Divinopolis. You can use a Brazilian airline for flights within the country.
Near Divionopolis are two colonial towns worth a visit--Ouro Preto and Congonhas--and the big city of Belo. You can read about these places in guidebooks or online.
If you have time and are able to venture further west I'd recommend a visit to Iguaçu Falls. You could fly there from Belo, but may need to connect in Sao Paulo.
And then of course there is Rio. The cathedral downtown, the bonde, the beach, Christ the Redeemer statue, Sugar Loaf, samba schools, and more. Again, all is in a guidebook or online.
Be sure to try feijoada--black beans and rice and smoked meats--and a Brazilian barbecue, churrasco. If you go to Salvador, there are other foods unique to that region.
If you have a Brazilian with you, great. If not mind your p's and q's in the big cities. Good luck. You'll have a great trip.
Let me know if you want something more specific.