You can't really learn consumer marketing like this. Hindsight is 20/20 -- successes like Instagram are mostly throwing spaghetti at a wall and seeing what sticks. B2B marketing is a little less luck-driven, but not that much. There's a lot of data-gathering, trial-and-error, etc., and what worked in the past for one product isn't going to work at a different time or for a different product.
If you want to learn product marketing, find opportunities to practice it in real situations.
