Dear Subash Maharjan,
Thanks for your question,
For Nepal passport holders need visa to enter VN, you can apply vis on arrival with us for 1 month single tourist visa
The service fee : 12$ / per ( not including stamping fee 25$ at the airport for single visa)
It will take 1 - 2 working days for normal case and we will send you approval letter which was issued by immigration Department and you can use this letter to get visa at the airport.
you can apply at this link: https://www.vietnam-evisa.org/apply-visa.html
If you need any support, please contact with us visa email: email@example.com or number phone: + 84 327 117 119.