Replace the placeholder sprite

To change your placeholder spriteA 2D graphic objects. If you are used to working in 3D, Sprites are essentially just standard textures but there are special techniques for combining and managing sprite textures for efficiency and convenience during development. More info
See in Glossary:

1. Click on it in the SceneA Scene contains the environments and menus of your game. Think of each unique Scene file as a unique level. In each Scene, you place your environments, obstacles, and decorations, essentially designing and building your game in pieces. More info
   See in Glossary View and then edit via the Sprite RendererA component that lets you display images as Sprites for use in both 2D and 3D scenes. More info
   See in Glossary Component in the InspectorA Unity window that displays information about the currently selected GameObject, asset or project settings, allowing you to inspect and edit the values. More info
   See in Glossary.

2. Replace your sprite via the Sprite Renderer Component in the Inspector tool.

3. Edit the Sprite field.

   You can click on the small circle to the right of the input field to bring up the Sprite Selector where you can browse and select from a menu of available 2D graphic assets.