Office 2016 is the latest version of the suite, and is designed to be used from the desktop. Office 356, meanwhile, is a larger suite that is cloud based. It contains the entirety of Office 2016 alongside other programs: in other words, Office 2016 can be obtained on its own, or as part of the wider Office 356.
Office 365 is a suite of integrated apps and services, designed specifically for business. It includes the office apps your business has already become accustomed to including apps like Word, Excel, PowerPoint, and more.
A product key with 25 Digit Alphanumerics like XXXXX-XXXXX-XXXXX-XXXXX-XXXXX is all you need to Activate and Setup Office from www.office.com/setup. The office activation code is unique for every office product and helps you to maintain the authenticity of the product. Once you complete the purchase of your desired product, you get this product either in an email (in case of an online purchase) or printed on your retail card (in case of an offline purchase).
Once you have downloaded the Office setup, the next step is to install MS Office on your devices. For this you need to follow the steps mentioned below:-