Hoi An is located centrally in Vietnam, and even though it doesn't have an airport, it is definitely connected. The nearest airport is Da Nang, and that is just a 45-minute push away. You will find a community bus which operates on a regular basis and only fees 1 USD, https://fernandoptsya.suomiblog.com/5-easy-facts-about-hoiinan-described-55427570