Windows Defender for Endpoint Deployment Plan
Based on your business need you can choose the Defender licenses. Defender license comes with the subscriptions plans.
Windows Defender for Endpoint Capabilities
Microsoft Defender comes with the 2 Different plan-1 and Plan-2, Here is the Plan capabilities.
Windows Defender for Endpoint Capabilities
Microsoft Defender for Endpoint plan include with the Microsoft 365 E3 and E5.
Here is License Cost with Teams cost.
Here is License Cost without Teams cost.
To get more details visit on Microsoft site
https://www.microsoft.com/en-us/microsoft-365/enterprise/microsoft-365-plans-and-pricing#plan_tab1