Based on you saying there are two forms of address, I think you may be Asian? Apologies, but I know several languages have professional and friend/ family ways of communicating. In English, we basically use the same for all but there are more professional ways to address someone you don't know or a coworker, etc. Basically, please and thank you, along with "may I" when asking permission or to be granted something a little out of the ordinary will go a tremendous way to being polite. I think the fact that you're asking these questions says a lot about you as a person that you want to be considerate. Best wishes and happy travels!