Depends on the situation. Formal would be "Posso ajuda-la?" (if the person you're approaching is a woman), "Posso ajuda-lo?" (if directed to a man) Another way would be "Posso ajudar em alguma coisa?" - Can I help with anything?
In Brazilian Portuguese, you can say "que o Senhor te abençoe."
The language spoken in Brazil is not called Brazilian, it is Portugese. If you re-phrase your question, you may get the answer that you seek.
"Grande" is how you say big in Brazilian Portuguese.
you say tchau
You would say "Eu sou brasileiro" in Brazilian Portuguese.
How are you in portuguese(brazilian) is "Como vai você?"
To say "my name" in Brazilian Portuguese, you can say "meu nome."
"Olá" is how you say hello in Brazilian Portuguese.
"Beijos" is how you say "kisses" in Brazilian Portuguese.
Brazilian(male)= Brasileño Brazilian(female)= Brasileñabrasileño, abrasileños, as
Brazilian is not a language, but Portuguese. And you'd say "por favor" (pronouncing poor-favor)
In Brazilian Portuguese, you can say "Oi" or "Olá" to greet someone.