
You can refer to the guide Disabling the Feed.
But for the Microsoft365 portal you can do it only via support request.
Disabling the Feed in Microsoft 365 (previously Office.com)
In Microsoft 365 (previously Office.com), as a tenant admin, if you want to disable the experience there, you can contact Microsoft via a service request to turn off Microsoft Feed. Turning off Microsoft Feed removes the Feed icon from the left navigation of Microsoft 365.
- Sign in to Microsoft 365 with your Microsoft 365 admin account.
- Select Support > New service request.
To re-enable the feature, you can create New service request.
Best regards,
Aleksandr
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