Regarding use of USA iPad 20w type c charger in india

it works with 110 volt AC 60Hz to 240 volt AC 50Hz

but unless india use the same connectors as usa then you will need a plug converter for it to physically connect to their ac connectors

Voltage Converter.....No

Plug Adapter....Yes

For India, you need a Type D adapter. Looks like this:

Amazon has them or pay twice as much in the airport shops.