Hi! My name is ***** ***** it is my pleasure to assist you tonight.
Microsoft does not offer discs for Office 2016, so you will need to download the software in order to install it. Since you've already installed it once previously, it will be registered to your Microsoft Account and be re-downloadable from:
If you are unable to successfully download or install from the above site, please post back with more information re: the error you're seeing so we can help you through it!