How to use Cinemachine as a follow camera for platformer in Unity
Lets’ go over how to use Cinemachine as a follow camera.

Add Cinemachine package to your project following the steps in my previous article.
Add a new virtual camera to the scene:

Select the camera and drag the player to Follow target:

Lastly, set Body to Transposer and Binding mode to “Lock To Target On Assign”. Adjust Follow Offset and the damping as desired:

Good Luck!