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?
There is no significant loss in total skill with each newer generation. The paradigm is constantly shifting. Humans have always adapted and learned to manage whatever is readily available to them and how to maintain it. Your parents complain you don’t know their vintage skills. You complain they aren’t learning new skills. You complain younger people don’t know your “necessary” (vintage) skills.
“The children now love luxury. They have bad manners, contempt for authority; they show disrespect for elders and love chatter in place of exercise” - some guy in 1907 summarizing Greek beliefs.
The generation that can navigate whatever it is kids navigate (flipper zero?) can’t modify an OS. The generation that can modify an OS probably can’t tune a carburetor. The generation that can tune a carburetor probably can’t change a horse shoe. Your skills are based on what you have to do every day. As technology removes the need to manage those things, the skill is lost and new skills replace it.