I'm from India, planning to do Phd in Marketing Management. Can I pursue it with my job thats 5 days a week 10 hours a day?
Anything is possibly, but a PhD is a full-time occupation, so holding a job that demands fifty hours on-top seems infeasible. Even for a part-time PhD, you'd be working a lot of hours.
(Assuming a part-time PhD plus a full-time job is equivalent to a full-time job with fifty percent more in overtime is a fallacy in my mind. As is assuming two part-time jobs are equivalent to one full-time job.)