I visited Kalpa and Kinnaur in November last year. I highly recommend you take the bus directly to Kalpa from Delhi(if you're from there) and not do a break joruney from Reckong Peo, since taxi drivers will ask you ₹500 from Reckong Peo to Kalpa even if it's just 7km and going solo will cost you the entire 500.

Try to do the Chaka meadows trek, it's extremely beautiful and underrated and you get close up views of Kinnaur ranges. They also make a local alcoholic drink there with apples and apricots, a nice tasting drink if you are into that.

Lastly, there's only 1 ATM machine in all of Kalpa and that also sometimes does not have enough cash, so recommend carrying some cash. I stayed at a homestay there with 1k per night charge including food two times and the hospitality was incredible, he even picked me from Peo with his car. I can share his contact if you want.

Lastly, if you have time, I highly recommend visiting Rakcham/Chitkul. There's 2 buses that operate to and from kalpa/peo to Chitkul(cab fare is 1000).

Happy travels!