Hey Bharadwaj

you can learn English in two months and speak effectively in two months, but fluency needs time and Practice. In order to learn english, you have to first learn the grammar well.  You may follow John & Martin for learning grammer, Comprehension etc. Try to read English Story Books and underline the difficult words, search their meaning in the dictionary and try to make sentences with those words. Read English Newspapers, if not the whole article, just try to read and understand the headlines. Listen to English News, Movies ,songs etc, if you are having difficulty with the pace , try to read subtitles and understand what they are saying.

Along with this, try doing translations. Take a paragraph in hindi(or your mother tounge)and try to translate it to English.

Try speaking to friends or anyone who know english in english, if you do not, you will never  get the fluency. Also, try to think in english, it might sound odd but whenever you talk to yourself or think, try and do it in english.

Make shorter sentences, that way, the probability of you making errors will be less. Later, you can make normal or longer sentences.

hope this helps

.Dear Student

If you speaks English fluently then it will add a different flavour in your life . Firstly you have to learn all types of tense properly. As you know if you speaks English fluently then you can express yourself in interview very professional way .Then you have to focus on vocabulary.If you are dedicated in learning English then you can done with this in only 3 months.

Thanks.
All the very best