Once you start digging deep enough into problems to make a difference there is not enough hours in the day to be more than a dilettante in a more than a limited set of topics.

One does need some general skills, some of those listed above, but you'll definitly need first aid skills like stopping bleeding before learning how to set a bone. School is about the only place that systematically teaches general skills to everyone, not just people with paretns with enough time, skills and energy to do so or hire someone to do that for them.