Before you start your preparation classes, make sure you know what is in the IELTS exam and whether the exam is right for you. There are many other English language exams available.
Look at the official website:
Do you need IELTS Academic [for applying to a university or professional registration] or IELTS General [usually for migration to an English-speaking country]?
What band score do you need? Here is information on the 9-band scale: