Flight ticket in Pokhara

Can we buy a Kathmandu-Delhi (one way) flight ticket in Pokhara 2-3 WEEKS advance or must we go to Kathmandu to buy? Or can we buy them in Kathmandu 2-3 DAYS before we want to fly?

You can certainly buy tickets in KTM. Doing do over the internet is next to impossible, so you'd need to find a travel agent who will do it for you. There are quite a few flights per day.

You can book flights in Pokhara and Kathmandu. Flights might be a little cheaper if you book 2 - 3 weeks in advance. There are loads of travel agents in Pokhara and Kathmandu.

flights b/t ktm and delhi are booked up for the next month or two. plan in advance.

if you need a flight alternative, you can always fly via calcutta. two tickets then, will cost a bit more, but you can choose your dates.