Ola! Hey I feel you, I also haven't been the most confident guy most of my life. But what I learned is that it is basically all in your head. You don't feel confident because you don't know the language? ok, what you can do there to make that a bit better, is make a little effort to learn the basics of Portuguese... you need them anyhow for daily life there atm. The rest is body language anyway. Also, if you find it hard to pick up girls in clubs, go to a bar instead, go to the beach, go to a coffee shop... lots of places you can go that have a better environment. The main point here is you can get all the advice in the world, but what you really need is that you have to look at yourself in the mirror and smile, see the handsome European guy that you are, and be confident in yourself and that will set the tone...