Languages

Let's start decoding your problem related to MBA. Master of Business Administration (MBA) is a postgraduate programme. If you want to make a career in business administration or grow your business strategically then MBA is quite a good option. Now, let's talk about the premier institutes offering MBA are IIMS, XLRI, SP Jain, Narseemonji, Symbiosis, IIFT and many more.
Admission Criteria: Bachelor's degree in any stream (if you want to get admission in IIMs or another good institute then you must have a good educational background).
Selection Process: You need to qualify Common Aptitude Test CAT for IIMs, and XAT for XLRI. There are other entrance exams like MAT, NMAT, etc. But it's better to prepare for CAT as it is excepted by all institutes. Syllabus of CAT is Verbal Ability, Logical Reasoning and Aptitude. As you said that you are not good with your English then I would suggest you to start working on English grammar, create a habit of reading by reading articles in the english newspaper, learn new words in English. Try to read books by different author. If you want a proper guidance then I would suggest you join a good coaching institute. Ask them to help you. There you will get proper guidance and mentorship.
I hope I made it simpler for you to understand the important points related to MBA.
Feel free to ask anything.
Good luck.