"Yes, you need to have a Microsoft 365 E3 or E5 subscription to use Copilot. However, you don’t need to pay extra for Copilot if you already have an E3 or E5 subscription.
According to the Microsoft Community Hub, Copilot users must have either a Microsoft 365 E3 or E5 license and an Azure Active Directory account. On top of that, users must be assigned a Microsoft 365 Copilot license using the Microsoft 365 admin center (under Billing > Licenses) . I hope this helps!