What's a skill that's taken for granted where you live, but is often missing in people moving there from abroad?
I was thinking about that when I was dropping my 6 year old off at some hobbies earlier - it's pretty much expected to have learned how to ride a bicycle before starting school, and it massively expands the area you can go to by yourself. When she went to school by bicycle she can easily make a detour via a shop to spend some pocket money before coming home, while by foot that'd be rather time consuming.
Quite a lot of friends from outside of Europe either can't ride a bicycle, or were learning it as adult after moving here, though.
edit: the high number of replies mentioning "swimming" made me realize that I had that filed as a basic skill pretty much everybody has - probably due to swimming lessons being a mandatory part of school education here.
If you aren't from south / southeast Asia you'll struggle with our traffic. Our roads are a stream of everything from cycles to busses with no dedicated lanes. If you want to cross the road and can't find a zebra-crossing you gang up with other pedestrians, hold up traffic by shouting and waving, and cross.
Understanding languages you don't know - every city will have people speaking three or more languages, so you need to understand what someone is saying even if you don't speak their language. Broken English with gesturing is a lingua franca.
When I was in Vietnam I just walked out and kept walking at the same speed while trying to get eye contact with the drivers. Worked good.
Yes, this is how you do it. Actually it is a lot safer than it might look.