A family of Microsoft word processing software products for creating web, email, and print documents.
You posted in the "for business" category. Is that correct? Note that for business (organization) subscriptions, the local Office admin may have set options to control Copilot. The option cannot be changed by an individual user. In other words, you have to talk to the admin in your organization.
If you are an admin, take a look at the settings in admin center. Go to https://admin.microsoft.com and sign in with your credentials.