I think one big difference between learning marketing vs learning software engineering is the lack of a feedback loop when you start out.

If you want to learn marketing properly, it's worth thinking of marketing tactics and marketing strategy as two different things. - Marketing tactics are things like, running ads, writing content for SEO. Comparable to writing code day to day. - Marketing strategy is the high level application of research and marketing science. Comparable to system design.

If you jump straight into tactics, growth hacking, posting on social media etc, you might learn how do some things, but you won't know why things work, and you won't know why generic tactics you read about on line maybe aren't working in your scenario. This is in the same way that you can learn to code online, but if you're only ever copy pasting from tutorials and stack overflow, you're going to get messed up with N+1 queries.

I would suggest getting a base level of understanding the core marketing science that exists. For this I would suggest reading anything from the Ehrenberg Bass Institute. In particular the book How Brands Grow, it's a bit dry, but very approachable.

https://www.amazon.com/How-Brands-Grow-What-Marketers/dp/019...

The Ehrenberg Bass Institute has quantitative marketing/advertising/brand results going back to the 50s. If you're interested in the math, I recommend checking out How Brands Grow by EBI director, Byron Sharp.

[1] http://www.marketingscience.info

[2] http://www.amazon.com/How-Brands-Grow-What-Marketers/dp/0195...