NullReferenceException: Object reference not set to an instance of an object CameraMovement.Awake ()

hello, I’m a beginner in Unity, I just finished Camera Movement (I’m making a 2D game) and then the game threw me this error: NullReferenceException: Object reference not set to an instance of an object
CameraMovement.Awake() (at Assets/C#/CameraMovement.cs:11)

i followed the tutorial step by step and i have CameraMovement script attached to Mein Camera.
I am sorry for my bad English

Always the same answer, ALWAYS.

How to fix a NullReferenceException error

https://forum.unity.com/threads/how-to-fix-a-nullreferenceexception-error.1230297/

Three steps to success:

  • Identify what is null
  • Identify why it is null
  • Fix that