Follow these steps for How to Upgrade Microsoft Office:
Method 1: Upgrading Microsoft from 2013 to 2016
Go to the Microsoft official Account page. It's from https://login.live.com/. Since Microsoft doesn't typically save your login details, you'll likely need to log into your account.
If you're already signed in to your Microsoft account, skip the next two steps.
Type your email address, then click Next
Enter your password, then click Next
Click Services & subscriptions
Click Install Office
Then, Click Install
Double-click the Office install file.
Wait for the installation to finish
If you are having any issues after following these steps. You should call our Microsoft support phone number. They provide the best support within a short time.
Read More: Microsoft office support phone number