That's how I learned Korean in my household. What my parents did was that everyday when I watch TV they would put on a cute Korean kid's TV show. And when the TV show is a bit complex for my level they would get subs on it, so I can read it and be able to hear the Korean ver.
On the English one. It's best not to force him to enjoy something, do a gradual change, but still keep the English shows on for him. And specking the 2nd language around him is another good idea -would be much better if you could have spoke the 2nd language fluently.
I'm not sure about the learning it in 2 or 3 years. Even by doing the same thing as this I still am not fluent in Korean, but by a couple of years he should get a decent grasp on it.
In my experience it is perfectly possible to learn a 2nd language by watching cartoons only. I learned English by watching cartoons and this opened many new doors for me. However, it took around 5 years for fluency to develop.
E.g. My earliest memories of watching the British version of Cartoon Network is at around age 4, while I realized I could speak and understand at around age 9. In terms of screen time per day, I would say the TV was on all the time, although I would only focus on it for 3-4 hours on average.
This would sometimes include documentaries in English as well (again, quite useful), so I was constantly exposed to it. I ve recently graduated from a university in Scotland and I have so far met 20+ people who learned English the same way, many of them coming from a variety of cultures and backgrounds. And these are just the people who happened to share how they learned English.
Additionally, the level of understanding is also considerable. I started formally studying English in school at ages 11-13 and then again at ages 16-18. By the time I started, I already had an intuitive grasp of the language so was bored all throughout my classes.
You may get a better sense of what I mean from the following: I had a score of 107 out of 120 on the Test of English as a Foreign Language (TOEFL) without any additional preparation. So I certainly think there is more room for cartoons when educating children in a foreign language. Hope that helps.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.