Improve enormously in English?

Hay I'm currently trying to improve myself in English as I'm a private student and at school a rivet.

I watch every evening on Netflix series / Youtube videos with English pronunciation and German subtitles, I also read some English books and listen to English music. Yet I do not feel any great change in my vocabulary.

Am I doing something wrong? Where should I change something?

Video games and old.reddit.com for active voice use

You can also watch anime with English subtitles quite easily, as the subtitles often appear in the footage and you can even remember the words better.

English YouTube videos are not that bad. But I have had no experience with it, then to look with German subtitles. What if you're doing English subtitles and the words you do not understand look up with Google?

Personally, I also read books, but it is suggested that you only read books where at best you come across 1 unfamiliar vocabulary per book page, otherwise it will overwhelm you.

If you're / were 10th grade, Harry Potter would be just as readable (B1 level).

It is difficult to improve one's abilities in a foreign language only by listening. It's not just about the vocabulary, but also about the sentence structure. In order to speak / write in a foreign language, much has to happen in the mind at the same time. What do I want to say, how should the sentence be constructed, what words do I need for that now? And that should be spontaneous.

It helps to thoroughly follow the grammar rules. It has to be in your flesh and blood. That needs meat.

In German I never had the problem, but in English I really wanted to improve. So I grabbed a textbook and worked through the grammar rules again and again with their own example sentences, and also written down until the grammar sat. That was a few weeks of hard work.

Every day I spent two or three hours doing that, and certainly wrote five exercise books, but it was worth it. I started with the simple declarative sentence and interrogative sentence by all persons, and systematically worked my way through all sentence forms, with all personal pronouns, times, cases, etc.

Later I moved to England, and of course I still lacked a lot of vocabulary. But still many locals were amazed at my perfect sentence formation, which was even too high for some.

Which textbook can you recommend to me?

I can recommend you to get an exercise book that will improve your vocabulary immensely.

In addition, you should try to make your everyday life in English by talking to friends in English, thinking in English, etc.

You do not do anything wrong but abruptly can't change much the time and a lot of practice. Try to write texts to improve your listening skills and your pronunciation.

Meh, do not think much of grammar rules, even though I'm grateful for your effort.

I'm about at C2 level and have learned as good as 0 grammar rules. Some types of learning can be overcome by observation and reproduction.

Later I moved to England, and of course I still lacked a lot of vocabulary. But still many locals were amazed at my perfect sentence formation, which was even too high for some.

Well, that's the problem again as a language learner - mostly the native speakers themselves do not speak very well. Unless you want to become a book author like me, the mere memorizing of sentences will not help you.

And it did not bring much if the vocabulary was missing.

You do not need a specific book. Just take some English book and work it through. You should think up example sentences yourself and take the rules as a blueprint. This will also train you to use your vocabulary in correct sentences.

Anyone who comes to a country whose language he has learned as a second language will certainly not know a number of vocabulary. But if you know the structure of the language from the FF, then it can be much easier to acquire. What I still lacked at the time was the jump from C1 to C2. So you can put your toe where you want.

It's also a talent question, whether you have to buff grammar rules, or who can learn so by the way.

Well, as a talented person, I can't imagine the other state.

I myself was not yet in another country, but I'm sure that I would get there.

Test from about 2 years ago where I was just before 18 (and was there from the level to the limit of C1 / C2, should now be low-C2)

* https://www.efset.org/de/english-certificate/plus/ 2 hours test

Here's a half-incomplete list of words I understand, some C2 and C1, sometimes forgetting to enter them when I see them.

https://dictionary.cambridge.org/plus/wordlist/12138102_what-words-i-understand

It's just a bit depressing when you have to sit in a high B1 / low B2 class because of the school curriculum and it's far too easy. Just wanted to drain frustration here.