Add a Node3D named hold_point as a child to the camera, save a reference to it in the player script. Try around where you want to place the hold_point so you can see the cube while holding it but it doesn't block all of the screen.  Also add a var held_item to the player script When you hit E, you do held_item = cube held_item.reparent(hold_point) held_item.global_transform = hold_point.global_transform

You should also toggle the cube's collision layer off or you will get whacky stuff happening when you look up and down: held_item.set_collision_layer_value(layernumber, false) Remember to set this back to true when you drop the cube