Office 365 subscription plans are month/yearly subscription based purchase you can create with the premium versions of the Office applications like Word, Excel, PowerPoint, Outlook, as well as access to additional features like business class email , SharePoint and online storage with OneDrive, Skype minutes and other tools When you have an active Office 365 subscription, you always have the most up-to-date version of the Office applications and can use on up to 5 devices PC or MAC or Mobile device.
Office 2019 is a one-time purchase with the classic versions of the Office applications such as Word, Excel, and PowerPoint for use on a single PC or Mac. The applications are not automatically updated;