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.
Simple math like additions and subtractions. Giving change back seems like trigonometry for some. (Note, I actually do enjoy trigonometry. It’s so much easier to calculate angles with fractions of Pi than the random 180°)