Aviation

Most of the airlines in India have an approval for their own training establishments to train flight dispatchers, usually as an upgrade to their existing operations executives. A self-sponsored flight dispatcher course in other institutes without being employed at the moment is not a great idea in my opinion. Since, it involves passing DGCA exams and an OJT after which would be the viva to be approved as a dispatcher on a particular type of aircraft.
However, in case you decide on doing the course anyway, Air India's Central Training Establishment (CTE) has the best standards of training and commands good repute. Since, the flight dispatchers license is aircraft type specific (A dispatcher licensed/ approved on an A320 cannot dispatch a B737 for example) and CTE trains on the A320, it is an advantage considering the type operated mostly in India is A320 (Indigo, Go Air, Air Asia India, Air India and Vistara).
You need to be mindful, if joining private institutions and thoroughly check, if the institute is DGCA approved. There are many private institutions claiming FAA approvals are scamming young candidates claiming bright future in the apparently glamorous aviation world, but that certification in India is of no use at all.