Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Brussels Bruxelles-National Airport to Dharamshala as you normally would.
If you book a flight to Dharamshala from Brussels Bruxelles-National, you will be flying to Kangra, which is the city’s only airport. Dharamshala Kangra (DHM) is located 8.2 km from the centre of Dharamshala. There are 0 flights from Brussels Bruxelles-National to Kangra per day from 0 different airlines.
These are just IATA (International Air Transport Association) codes. They are used in aviation to identify and differentiate airports. That’s why a Brussels Bruxelles-National Airport to Dharamshala Kangra Airport flight would often be abbreviated as a BRU to DHM flight.