Surprises for foreigners? Some, from talking to foreigners : 1) British people will form a queue of one; themself and nobody else; at a bus stop, standing obediently by the sign.
2) Jumping the queue is met with a chorus of tutting and remarks to be overheard as "Some people have no manners!". It is rare for the offender to be confronted; they are meant to be shamed out of continuing
3) Nothing anybody English says is to be taken literally, it is anything but, from simple irony to self-deprecation and understatement ("I did swim a bit when I was young", may = I won gold at the Olympics; "I have a place in the country= I own Chatsworth" etc).
4) British men will introduce male friends with abuse "This is Tom. He's a right c***" means "He's my best friend/brother"
5) There is an invisible queue in pubs. The staff are expected to know who is next. If they get it wrong, you are expected to say "No, this lady/ gentleman is first". You will never understand how this works.