Buying in Thailand to be shipped to a Thailand address from online store with Indian credit card from India.

I want to buy airpods pro 2nd gen from the online store of Thailand and send it to a Thailand address to my sister, but do the transaction from India. Is it possible?

No.

I can't read the Apple Thailand store pages, but on the Apple India page it is made clear in Card Payments - Shopping Help - Apple (IN) that Apple.com only accepts payments from cards issued in India, the United Kingdom, and the United States. Apple can only deliver within the same country you’re ordering from.

Something similar appears on the Apple US site at Shipping & Pickup - Shopping Help - Apple:

Items purchased online from Apple ship within the continental US, Alaska, Hawaii and Puerto Rico. No shipments can be made to P.O. Box addresses, United States territories, or addresses outside of the United States.

Reading your query again opens that doubt. Try it, the store can only say no. However, it depends on what the Thai store's policy is and although it's likely to be similar without having access to this it remains questionable.

The card is the limiting factor I suspect.