How I can learn English language very perfect
If you use English more and more, you will definitely improve. Speak it, read and write in it, and listen to it (TV documentaries have speakers who speak slowly and clearly).
When it comes to studying grammar, have very clear objectives why you do it.
My suggestion is to first aim at avoiding common grammatical mistakes. For this, you need only to learn the basic rules of grammar. Don't get sucked into the finer points or too much terminology; that's for language specialists who like to analyse and invent (sometimes ad nauseam, to not much practical use for teaching the language to others).
Your second step and purpose in learning grammar is to widen the range of your expressions; learning grammar rules helps with increasing this skill.
Don't learn grammar for the sake of being PERFECT in telling whether a word is being used as (say) an adjective or an adverb. Just learn HOW words are used, and knowing the essential grammar rules helps with this.