Welcome aboard! What trade are you in? I imagine it's a pretty demanding one.
Well not to brag but in plumbing you gotta know pretty much everything, carpentry to install the tub/shower, electrical to hook up the furnace or a/c unit, heck basic health for when the coworker does something stupid and you have to rush to help, lol..JR
I'm a plumber by trade...
For myself add all the machines for auto manufacturing & medical industry stuff med gas etc.