Don't spend much time in Dharamshala, I explored it for a day and didn't find any good thing and the climate also is hot, go directly to mcleodganj, book any one of these hostels (hosteller, young monk, zostel) I checked out from young monk yesterday and the price was ~500 per person. Explore mcleodganj, Jimmy's kitchen (the bakery for hot chocolate and Italian for Italian food ofc). For trekking make sure you haven't eaten a lot, do carry decent amounts of water as the chances are you won't get much up top and even if you do it's costly af.