I have just bought an Apple TV 4K from USA. but the power cord says 120v how can I use in INDIA ?

My own US-model 4K is labeled (on the bottom) 100-240 VAC, 50-60 Hz.

If your’s is similarly labeled, it will safely “power up” on India’s standard “mains” power with only a physical “plug-style” converter being needed.

The “wall plug” style of the cord (NEMA 1-15P) is what technically determines the cord’s “nameplate” marking.

However, the U.S. style cord will perform perfectly well and completely safely at 240 VAC / 50 Hz.

However, If you’d prefer, you can no doubt obtain a cord w/ a factory-installed “Indian-standard” connector at the “wall end.”

Good to hear.

Enjoy your new hardware!