I will have to tell you ,that you can't say 'How to became nice English?"
I think you need to start learning English from the scratch to know how to use words correctly and build correct sentences.
You better start by taking some lessons online or in real life to get introduced to the language,learn some basic grammar, vocabulary and build simple sentences.
The following are further tips to help you improve your English on the long run :
Here are some tips to improve your English skills on the long run.
They are some methods among others ,not necessarily the best. You choose whatever suits you and be innovative in finding out about other methods you could apply to help you learn quicker and more efficient.
As for the following tips ,intensifying your efforts will help you improve quicker and master the language on the long run. Just practice them and don't give up or loose confidence. It is a matter of persistence and hard work.
*Reading at your level of comprehension simple texts or books and looking up new words .
* Listening to English through music and possibly reading the lyrics.
* Watching movies in English with subtitles in your mother tongue..
* Chatting with natives online using voice chats or in real life .Mingling with natives is a very good way to be constantly listening to speech in English, even if you don't understand at the beginning.