if youre struggling visualizing it, try reducing the size of a reference down to pixel art size. this will give you an idea of what it would look like if you pixeled by hand. though if you do reduce it, note that it has to be significantly retouched to be considered pixel art. generally you should only reduce it to get ideas, then do it yourself manually.
I showed what the ref looks like reduced. then introduced color i might add, because it is good to have contrasting hues in pixel art because your palette is small. the 3rd example is an idea if you were to get artsy fartsy with the colors. Note that none o the 3 below examples are pixel art. Just an idea of what the ref might look like if it were like 50% done
Your pixel technique is lacking currently. I suggest working at a much smaller size to learn proper pixel control. I also suggest an easier thing to create, as a moon and clouds is really really hard unless you go with a very simple style
