It’s a visa that you can get at one of the three international airports in Vietnam (Noi Bai, Tan Son Nhat International Airport or Da Nang) and you can only get it if you enter and Vietnam Male by air.
Specifically, Vietnam Visas when applied to people traveling to Vietnam by air and get a visa at the airport when you have a contraction approval from the Immigration Department’s management Vietnam.
When you arrive in Vietnam in the international airport, you can get a visa and pasted into your passport at the counter of the Immigration Department by the approval letter together with your passport (6 months effect), two 4x6cm-sized photographs (taken within six months must) and fees (you must pay this fee in cash).