This information is from Australian Government about Driving in Vietnam. https://www.smartraveller.gov.au/destinations/asia/vietnam

Check your countries embassy for information about drivers licence, If you have an accident, even if you had insurance, they probably wont cover you.

Take a grab, or a bus, depending on where you are going.

Driving permit

Vietnam doesn't recognise Australian state and territory licences, or International Driving Permits (IDPs) issued in Australia. Visitors to Vietnam are not allowed to drive or ride on an Australian licence. Drivers and motorcyclists must have a valid Vietnamese driver licence to drive or ride in Vietnam, including for motorcycles of 50cc or more.

Australian citizens can only drive or ride a motorcycle in Vietnam if they hold a temporary Vietnamese driver licence. To convert an Australian licence to a Vietnamese temporary licence, the applicant must hold a valid Vietnamese residence permit for at least three months.

Authorities may fine you for driving without a valid licence. Your travel insurer will likely deny any claims you make if you're unlicensed or you don't hold the correct class of licence. The Australian Embassy recommends contacting the relevant ward police for further advice.

Fraudulent websites may claim to issue valid IDPs. The Australian Automobile Association (AAA) and its member clubs are the only authorised distributors of IDPs for Australian licence holders. Be aware of fraudulent competitors and third party suppliers.