Part 1
A: Enjoy yourself and learn.
So you want to improve your English. Do you need to improve your English for work reasons, for study reasons or for personal reasons? Maybe you just want to understand better when native speakers are talking. Or perhaps you want to be able to express yourself better. Do you need to write English better? You may want to read more quickly. Do you need to talk on the phone and carry on email correspondence with people in English? Do you have to make sales presentations in English? You may often have to take part in business meetings in English. You may want to attend a university in English. Are you preparing for a major English test like TOEIC or TOEFL or IELTS? Maybe you want work on your pronunciation. Perhaps you just want to know more words.
It really does not matter why you want to improve your English. The important thing for you to know is that you can improve. You can actually improve quite quickly. You just have to do it the right way. Most people study languages the wrong way. They study from text books or traditional learning systems with uninteresting content, but lots of pictures, plenty of grammar explanation and quizzes. This kind of instruction looks like it should work, but for most people it does not. It is uninteresting and inefficient. Most people do not progress rapidly and are not satisfied with their language studies. They lose interest and will only study if forced to because of exams. I can understand this. It is hard to keep working at something if you do not succeed.
You need to understand how to learn a language. When you learn a new language your brain starts to change. The brain begins to build networks of neurons that will enable you to operate in a new language like English. You will not become fluent because you understand grammar rules. You become fluent as your brain naturally develops the ability to understand English. You become fluent when you can put thoughts together correctly in English without having to try to remember grammar rules.
So how can you most quickly build these new networks for English? It depends on three things: your attitude towards studying English, the amount of time you spend on English, and how efficient your study method is. It does not depend on teachers or tests. You have to realize that your thoughts and actions are what will most influence the development of these new networks in your brain. How well and how quickly you learn is up to you.