Latest travel protocols to enter Nepal.
01: There is no quarantine rule for fully vaccinated travelers, but they need to make sure that they have received their last dose at least 14 days before they enter Nepal.
02: On arrival visa service has resumed for fully vaccinated travelers. Need to present the following documents at immigration:
A: Vaccination Certificate with proof of 14 days after the last dose
B: PCR negative test issued within 72 hours or less before first flight
C: Proof of hotel booking.
D: Copy of filled International Online Arrival Form available at CCMC website (Print). (https://ccmc.gov.np/arms/person_add_en.php)
E: Copy of mountaineering or trekking Permit.
03: There is no arrival visa provision for non-vaccinated travelers. They need to have a prior visa from Nepalese Diplomatic missions in their respective countries.
04: Non-vaccinated travelers need to stay 10 days in quarantine at their own cost in the hotels designated by Nepal Government. https://www.tourismdepartment.gov.np/pages/notices/33/195
05: Upon arrival, non-vaccinated travelers need to present all the documents specified in no. 2 (except vaccination certificate), plus proof of quarantine hotel booking.
06: All travelers should have a rapid antigen test while entering Nepal. If found positive, they should be in quarantine at the hospitals or isolation centers designated by Nepal Government. (Self Payment) 10 days.
07: PCR negative 48 hours before departure time. (For departure).
Also you may have more information from Nepalese embassies in your location.