Never and none, really.
My route was through a summer job, working at a golf course when I was 18-19: mowing greens, cutting hole locations, cleaning up roughs & hazards.
It only took a few days for an early concept of gca to take hold: how differing pins changed the way the hole played, the contours of one green in relationship with the rest of the hole & relative to the other greens-golf holes, where the drainage problems/puddles were and weren't, that one tree-lined 75 degree dogleg, how elevation changes were cool etc.
Walking around the course all day, watching for/waiting on golfers (and errant shots) and then late in the day playing it with borrowed clubs:
well, all of it helped form the idea that you don't really ever "just play golf", you always play golf "at this/that specific course".
And then later of course there were books and discussions on here, with architects & experts clothing that initial experience in erudite-detailed language.
Peter