Hi Udit,
You ask a number of good questions - and the specific answers that you're looking for will depend a great deal on the industry that you work in (and the potential companies that you might want to work for in the future). As such, you might consider reaching out to people who currently hold the types of jobs that you're interested in and ask for advice/mentorship. Those professionals likely have specific insights into the 'path' you should be taking to achieve your career goals (including which Exam you should take, Schools/Programs that you should consider applying to, etc.) - and having that perspective could help you to plan out all of these important steps in a more efficient fashion.
1) Assuming that you wanted to start studying soon, when do you think you would want to apply to Schools?
2) Going forward, how many hours do you think you can consistently study each week?
GMAT assassins aren't born, they're made,
Rich