Step 1: Open any office applications (Word, Excel, PowerPoint)

Step 2: On the top left, click on File, then click on Account at the bottom left.

Step 3: Below the product information, click on Update options, from the list of options click on Update now.

Step 4: It will then check for updates and download will begin once an update is found.

Next:

Microsoft 365 Apps - Registered Devices