When no object is selected the Scene Properties appear in the Inspector on your right. You can also select the Scene in the Object List on the left of the screen.
The Scene has the following properties:
First, you can click on the color box to change the sky’s color.
Click the left arrow next to the label to view more options for this property.
The first option is the Shader. It’s set to Standard by default, meaning that it will be affected by any lights in the scene. If you want the Sky to ignore the lighting of the scene, change this setting to Flat.
Sky Image Source
To set an image for the sky, click the Src button. We recommend an equirectangular image for the most seamless look, but normal images can work too depending on your goal.
Sky Image Repeat
If you’re goal is to have more of a pattern for the sky’s image, you can set the x and y repeat values here. Enter the amount of times you want the image to repeat/tile in each direction.
Fog by default is set to 0, which means it’s turned off. To enable fog, change its Far value to be greater than 1. A good value is around 45 or 55 (meters).