Word, Excel, PowerPoint, and all other applications included in Microsoft 365 (formerly Office 365) are automatically updated by default. Since automatic updates don’t always work perfectly, it’s a good idea to check for updates yourself.
Open one of the standard Office applications, such as Excel, click on File, and select Account from the left-hand column. In the right pane, click the Update Options tile and select Update Now to start the update check. If there are updates, the program will download and install them automatically.
Although the Download Office updates window also says that you can continue using Office, you should close all applications, since when you start to install an update, you will be prompted to close all open applications anyway. When the process is complete, you will receive a message that everything went OK.