There are several different reasons why you would want to uninstall Office 365 from your computer. You could be having issues with the program and must reinstall the program, you could be changing to another program or model of office such as Office 365 or OpenOffice, your subscription period could be up and you do not want to renew or it could be you want to use this program on a newer computer.
Whatever the reason the guide linked below will take you through the various ways to do this, ranging from the easy to complex as you go through the guide.
Microsoft Support website has guides to walk you through the different methods to remove Microsoft Office 2016 or 365 from your Dell computer:
Method I Uninstall using the Control Panel
Method II Uninstall using the Easy Fix Tool
Method III Uninstall manually
Click-to-Run - Streaming Installer
MSI - Microsoft Windows Installer
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