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.
Everything's a bottle opener.
When I built my house I made a bet with myself that I'd never open an end-of-the-day-beer with the same thing twice. I managed. I included the chainsaw, the backhoe and the crane (although I cheated that one and asked the operator for help).
Opening bottles with your phone used to be a thing too. Most used Nokias from the 32/3310 era in Denmark have scratches at the bottom from people not doing I properly. I've seen some people open beer with iPhones, but I wouldn't recommend it.