I suppose it would be mostly practical skills, cooking, fixing things. Usually had to be done by people themselves.
Maybe also mental things like navigating (with or without paper map) and remembering their daily and weekly agendas.
What other things would be a big difference with the people today?
I’ve got a log table in the back of one of my reference manuals. The results go up to 6 digits. You aren’t going to get appreciable material savings after 2 digits.
And in some cases like structural steel, the built up members were far more optimized 100 years ago compared to today because the labor required to build the optimized structure was that much cheaper.