Add Tilemaps to the project
Tilemap is a tool used for storing tile assets and build level designs.

- To make a tilemap, right click on the hierarchy, go to 2D object -> Tilemap -> Rectangular
- Try to play around with Tilemap section and see what each one of them does. But in this case, I'll use rectangular.

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After creating a tilemap heirarchy, go to tile pallet window and create new pallet.

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Once you create a new pallet, save it.
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I create new folder "Tiles" and save the pallet in there to manage it easily.

- After saving the tile pallet in the Tiles file, create a new 2D sprite by following the steps above picture.
- Then, drag the 2D sprite into the tile pallet.

- Lastly, add Tilemap Collider 2D componenet in the inspector window like above. This will add collider to the tilemap so the player can stay above it.
- Make sure the player has collider and rigidBody 2D applied!