I want to know if i purchase a Ryzen 9 5900x processor from the US and bring it to India then can I get warranty coverage in India
AMD Warranty on official AMD Retail Box processors is World Wide.
Just need to go to AMD Warranty and open a Warranty ticket if your processor is not working correctly or is defective from here: https://www.amd.com/en/support/kb/warranty-information/rma-form
Here is AMD Processor in a Box 3 year Warranty: https://www.amd.com/en/support/kb/warranty-information/rma-03