My friend I think you are talking about the preparation for CGL exam. Pls believe me. It takes time. You can only finish the coaching program in 3 to 4 months. But after that speed building is mandatory. You need to practice a lot. There 'll be a lot many errors, you need to rectify them. I don't wish to demotivate you. I really wish you crack the exam soon. But be industrious. You need to be ready to study everyday. I joined Vidya Guru. A lot of motivation came from the institute only. Exam will not be very difficult but you need to finish the exam in the given time and that's challenging. You have to score well to beat the competition. So I feel 6 months minimum (3 months coaching and 3 months practice) if you are an avg student but if you are above then you can crack it early too. My wishes are there with u.