You will get updates that fix bugs & security issues until 2025 but no updates that are improvements to functionality.No additional payments are required other than the initial purchase price.You can buy Office 2016 outright if you prefer. There is no such thing as a lifetime subscription.You can subscribe monthly or annually.These allow you to have Office 2016 at the moment and, provided you keep subscribing, you will be able to update to Office 2019 or whatever the next version is called.You are referring to Microsoft Office 365 subscriptions not Windows.
