One of the best and proven ways to learn the English language is through immersion. This means that you have to learn English immersion, live, breathe, talk, think and speak English.
Immersion will be achieved if you can live with a family who is willing to take you on. To teach you how to speak the language while staying with them. They also will have to remember that they do not speak your language to you except in emergencies.
Immersion can make you think using the English language. You will be forced to speak it. No one else will speak to you otherwise. Also, with helpful foster families or friends. Every time you speak with grammatical errors they can immediately correct your mistakes. You can learn faster from the mistakes by repeating the corrected way to speak the same sentence.
One of the exciting things about immersion is that you get to have to buy stuff. Dealing with other people who will only speak English to you. It only takes about a week before you start communicating in broken English. After three months you would be able to speak fluently. Even if there are still some corrections needed.
The minimum amount of time where immersion is successful is between three and four months, the most amount of time is about a year. Otherwise, you can speak and even read and write the English language, and speak it without an accent even.
Why does immersion work? The answer is simple. You are literally forced to think and speak in another language. Without anyone helping you out to translate. Meaning, the brain makes adjustments.
Does immersion always work? There are really some people who cannot learn any language despite immersion. The reason is simply because they refuse to learn and insist on using their own native language. They have a twisted sense of logic that other people will learn to understand their language if they keep on repeating it often enough.