How to see the hero through the wall (Tree)?

Question

Unity

The player plays for the ball (rolls it) when it rolls behind a tree it is not visible. I saw in other games the player goes behind the wall and the wall becomes translucent and the player can be seen through it or something like a window appears that moves behind the player when it is not visible and through this window becomes visible. I would like to do this, but I still don’t understand how. But I’m sure you can somehow through layers and LayerMask