The Vietnam Landing Visa is also called the visa on arrival. As the name suggests, it’s the kind of visa that you’ll get only when you arrive in the country. However, before you can get the visa, you are required to apply for the visa in advance. You are also required to submit some requirements at the landing visa counter in the international airport before they will give you your visa.
During your visa application, you will be asked to choose whether you want a single entry or multiple entries, which is great. Also, you can choose whether you need a 30-day or 90-day validity. Thus, this is the best visa to use if you are planning to stay longer in Vietnam.
https://www.vietnamimmigration.org/what-is-the-procedure-at-vietnam-airport-to-get-the-visa/
