Open your Outlook App on your Desktop.
Now Navigate to the Top left Corner and select the “File” Option to access the Account settings menu.
Open Outlook > Select File Options
Now select “Account Settings” to access the email account that you want to log out.
Files > Account Settings
Select the “Account” that you want to log out from the Outlook Application on the desktop.
Files > Account Setting > Select Email Account
When you “select the email account”, click on the “Remove icon” to sign out of the email account from your Outlook.