If you want to go there and have just enough of the language to say hello and be friendly with people, then all you need to do is buy a phrasebook, try to memorize three, four or five expressions and that’s all you’ll be able to do.
I had this experience when I went to Vietnam. After six or seven days, all I could say was thank you, please and goodbye, that’s about it. We just can’t absorb a lot of the language, at least my brain can’t, all that quickly.
However, if you really want to get into the language, which I highly recommend, there are 200 million people in Brazil. A great place to visit, or so I’ve been told.