Baglung Airport (BGL) has no lounge, and once you picture what this airstrip actually is, a short hill-country strip in western Nepal built for STOL aircraft, that absence is not a surprise, since there is nothing here resembling a terminal designed around premium waiting areas or gate lounges.
What Baglung actually offers is a small terminal building sized for a handful of passengers at a time, basic seating, and quick turnarounds between light-aircraft flights rather than an airline-schedule rhythm. Weather in Nepal's hill districts can delay or cancel flights with little notice, so the practical reality at a strip like this is built around waiting for a weather window rather than waiting in any kind of lounge. Bring a book and a flexible mindset rather than an expectation of comfortable indoor waiting.
For an actual lounge experience in this part of Nepal, Pokhara is the nearer real answer. Pokhara's airport serves as the regional hub for the wider hill and trekking region, with a larger terminal and more airline traffic than a strip like Baglung, though lounge provision even there stays modest compared with Nepal's main gateway, and it should be treated as a step up rather than a full premium experience.
Kathmandu's Tribhuvan International Airport is where the fuller Nepal lounge picture exists, as the country's primary international gateway handling the bulk of premium-cabin and long-haul traffic. Airline and pay-in lounge options there serve international connections in a way that regional hill airports were never built to support. If your trip includes both a hill-country leg and international travel, Kathmandu is the connection where lounge access becomes realistic.
Confirm current terminal facilities and any lounge access directly with your airline for both Pokhara and Kathmandu before you travel, since Nepal's regional aviation network is shaped as much by weather and terrain as by airline schedules, and details shift accordingly.