There is a Covid procedure and travel medical insurance requirement, that you can get update fro the embassy of Vietnam or the IATA airlines authorities country tracker
For the Vietnam Visa issuance
Case 1- Visa exemption, citizens of 13 countries Belarus, Denmark, Finland, France, Germany, Italy, Japan, Norway, Russia, South Korea, Spain, Sweden and the UK. Come with your passport no question asked.
Case 2- Visa under 30-day (mostly tourist visitors): for 80 countries, there is a new procedure e-Visa to alleviate the Embassies work, delivered by email within 3-days. If you go through a travel agency, they will arrange to get your visa for individual or group.
NB. For Extensions, you may submit the NA5-form via in your country VN embassy (more or less easy), in Vietnam immigration office or via a visa agency.
If you are not citizen of the 80 countries the usual procedure via the Vietnam embassy, travel or visa agency