Dear Pritish,
I would like to tell you that MPH is a postgraduation course that comes under health sciences. MPH course duration is 2 years. MPH course graduates get to work on a national and international level related to public health.
For eligibility criteria it's mentioned that bachelor's degree in any Health Science discipline, completed from a recognized university, hence you can opt for this course after completion of your occupational therapy.

I hope this information helps you

All the best