I have no Mac so I don’t know. But you probably would experience similar issues in other applications/games.
When posting code you should use code tags , not screenshots.
Since you use Rigidbody and apply forces to it, this should be done in FixedUpdate, not Update. Yet Input should be queried in Update. The usual “solution” for this is to set some bool or value via Update und query (and reset) it in FixedUpdate and apply forces accordingly. I suggest to look in the documentation about Unity’s built-in methods and to follow some tutorials about this topic.
And you should use KeyCodes not string equivalent (error prone).