Making a believable feeling of light is mostly about getting the values right. Color plays a role, as in the scene, above, but even with the color removed...
...the illusion remains.
Note that as the mountains step back into the distance, the range of values diminishes. The darkest darks and lightest lights are in the foreground. If the background shapes were as dark and as light as those in the foreground the sense of space would collapse. This phenomenon is not just a painter's trick, it is what we actually observe. The intervening atmosphere is full of reflective particles of moisture and dust that act like a translucent veil. The complexity of the scene also diminishes over distance, as you can see in the furthest mountain.
To be sure that the values you apply to each shape are relatively correct, remember to "bracket" the darks and lights by comparing them to each other. For example, the shadow on the mountain needs to be darker than the sky, but lighter than the trees in shadow. If you can't find anything darker than the shape you are about to paint, it must be the darkest thing in the scene. Converting the image you're working from to black and white makes this job easier, so go ahead and give yourself a break. Sooner or later, though, It would be good to know you can make value comparisons even when color is there complicating the task.
Feel free to make any changes you want, especially where you are simplifying the image. You won't really need to put in all the bricks, for example.
This one looks pretty easy, right? Can you please make it more apparent that this is hay, not rock?
Thank you, and have fun