Hello,
2 years is more than enough to clear any bank exams, even if you start from scratch. For building up your vocabulary and English language skills, start reading books, watch english movies. 'Word Power' is a good book which will help you in this.
For general awareness start reading any english newspaper, The Hindu or Indian Express are recommended. Also, watch news, read basics about our country, its geography, political structure.
For bank specific preparation, you can join any coaching institute, it will help you to provide a direction.
Have faith in yourself, you will improve gradually.

Good luck

Hello,

There's no need to feel so disheartened, you're very young and two years are more than sufficient to crack a banking exam, as you specifically talked about English, you can start with any Grammar book,the best is wren and Martin, get the foundation strong, for banking exams there's one book by SP Bakshi you can use that afterwards to analyze and evaluate your preparation and progress,another good book is word power made easy by norman Lewis,it's best for vocabulary building. For general awareness, I can say the best thing is to read newspaper on a daily basis, doing so will make you more aware of latest happenings and you don't have to worry about mugging up all at the time of exam, you can use The Hindu or The Indian Express, also if possible read any business newspaper The Economic Times as this will help you be acquainted with basic concepts of business,banking and other relevant matters, editorials are must ,because there's also descriptive session in banking exam,also nowadays Reading Comprehensions are directly coming from the Hindu, to build your knowledge you can also read Harvard Business Review,this will not only build your knowledge but quality or understanding of English will improve to a large extent.