"Do you know where I can find a public telephone?"
Translation:Você sabe onde posso encontrar um telefone público?
I had similar questions when I first started. To translate "I like to swim and walk" I would write "eu gosto de nado e caminho" because my thought was that I'm doing the swimming and walking so I should conjugate those as well in the first person. But it's wrong. Only the first verb is conjugated.