I moved to the UK (Scotland), as non native English speaker. Since then I discovered, for example, that when somebody offers you something, and you don’t want it, you can’t just simply say “No” (as in my native language). To not sound rude/passive aggressive you need to say “No, thank you”.
Similar problem, I was asked in free time by person in charge of me (manager) and who is two times older “Can I have a lighter, please”. If I translate this question to my native language, “please” in this case seems very submissive and is a big no-no in this exact question.
Same thing with ability to being able to speak “per you”/without adding title/small talk with older people or saying hi/hello, instead of more formal forms while greeting strangers.
Asking this kind of question in real world make me look like some ghetto man/barbarian, natives at first often don’t realize that some things are just different in different cultures.
The question is, can I learn about English language related manners not the hard way? How to not sound rude/passive aggressive without being too official?