Can I understand 95 percent of CNN, talk shows, movies and anything? If I listen to English materials (podcasts and videos, …) for three years and I also listen to English materials for 3 hours every day. I am a between B1 and B2 in the CEFRL scale right now.
Three hours/day for 3 years is over 3000 hours. That is a LOT of time, so, YES, you can do it if you take the right approach. You are already well past the beginner stage. But of course you will have to put in a lot of work to achieve your goal.
- Find a tv series or movie that you really love and are willing to watch many times. Your tv/movie viewing must be active and not passive. For example, when you encounter a word or phrase that you don't understand, rewind many times and try to understand. Look up words in a dictionary. Add new phrases to your flashcard deck so that you can review and not forget. Apply these principles to anything you listen to.
- Get a speaking partner, because this forces you to listen and then immediately respond to what you heard. Practice speaking/listening as much as you can (every day is best).
- Consider starting with easier material at first without immediately trying to understand CNN or complicated topics.
- Prioritize active listening activities over passive listening activities.
I am not sure about "anything/everything", but after 3 years of watching CNN, you will be able to understand standard American accent. You might still have issues with other American accents (southern, black american vernacular, etc), and non-american accents (some accents in UK are hard even for native speakers) especially if person has a strong said accent.
Years ago, I started with watching CNN (live TV so no pause/rewind), second hour was mostly a repeat of previous news so I was able to catch up what I missed first time around. CNN uses "neutral" American accent. But when I switched to NBC/Tom Brokaw (yes I date myself), I needed to adjust to his accent, which was more southern (not as neutral).
Also, I found that some of my friends who learned English by mostly listening, have hard time to spell correctly and use proper term (cell vs sell, buy vs bye, break vs brake, etc) so you may want to dedicate some of that time to reading.
I would suggest to start with articles in simple English with audio, like graded readers or Voice of America "Learn English" articles with video/audio (which are excellent: they use limited vocabulary - most common 1500 words - and explain the few new words). Listen first (without reading) to focus on listening comprehension, read later to confirm your understanding and learn the proper spelling. And check also BBC Learning English, also many hours of audio of different (British) accent, also worth to adjust to.
And maybe even in a shorter time. But you will have to push your limits. If you just listen to get a general idea about the material, you can watch and watch and your level won't improve. Indeed, some people live for years in a foreign country and have a language proficiency at the A-level (in the EU framework, that is, the lowest).
Search for material with subtitles. Watch first without reading, then try to understand every single word. Then, look up in the subtitles what they were saying to confirm whether you were right.
Don't focus too much on TV. On TV you have the images to help you understand the language and movies often don't have much dialogue in them. The audio is also processed, and spoken by actors with excellent diction. Go for talk radio instead. You will be exposed to lots of accents, thick dialogues that resemble real life interactions.
I would say that with B1-B2 you are almost there. In addition, reading and writing instead of only listening will improve your ability to understand spoken word. Because it will expose you to a greater vocabulary and will make you think about how to express what you want, in a clear and concise way.
So divert some of that TV time to the witten word, books, blogs, newspapers. Having said that, i think i learned a lot of english from listening to music and watching tv. English class in school was just dotting the i's and crossing the t's.
That is a very good practice. If at the same time you improve your understanding of grammar and syntax, and increase your breadth of vocabulary, you will be able, using the context, to understand almost everything. However that does not mean you will hear almost everything.
To expound on the last point, as a non native speaker your brain, it is likely, cannot distinguish between sounds that are not in your native language. And depending on your age and your natural talent, just listening to English will not be enough to make your brain aware of the different sounds.
So if you don't actively try to reprogram your brain to learn these sounds you will have to rely on context to understand what is being said. For instance, some languages have only one S sound, and people from these countries will not be able to listen the difference between sea and she.
To learn the different sounds, you will have, first, to become aware of the different phonetics and practice listening to them. One site that can be helpful for that is phonetics practice. Also, I would recommend trying to find out what are the phonetic differences between your language and English.
I have done the same, and it is what pushed my listening ability a step beyond just listening to English can achieve.