Read biographies of great people across all walks of life. Personally I got a great deal from reading about Thomas Edison, Richard Feynman, Winston Churchill, Nikola Tesla, etc. Also basic psychology, e.g. cognitive biases, Maslow's Pyramid, physiology. Watch documentaries about various industries, manufacturing, construction, etc. Understand basic accounting and finance principles.

The reason I suggest the foregoing is that technology changes at a rapid pace, but in my experience the majority of real problems stem from people factors, communications issues, biases, lack of critical thinking, perverse incentives, factors such as ego, greed, hubris.