Mountains

Hey, as was said already, when working only with values, commit to definitive value shapes. Simplify them as much as possible if you're struggling. Group them generously. It's also usually a good idea to start with as few values as possible. Try to represent your image with just 2 values first. Maybe add a third and see how it works. Try to do this gradually, working with one value at a time and not constantly jumping in between. Squinting when looking at your reference can help a lot to find the values. Otherwise, in digital, feel free to use tools to make identifying values easier while you're struggling. You can add a soft blur over the entire image to get rid of details that might confuse your brain in seeing the most important value groups. Or you can even use digital tools to reduce the total amount of values present in the reference if need be. Good luck!

your values are too similar so you're struggling to create contrast in your art. outlining with a lighter grey isn't helping if you don't have anything actually dark to make the light parts stand out. the stuff closest to the viewer can generally be the darkest/detailed while things further out is a lighter. (typically not always) When practicing I would also avoid blending until towards the end and don't blend everything just areas where the shadows are defuse, on rocks I think it's better to keep the shadows hard (because rocks are craggly) but this can be a stylistic choice smoother rocks like ones worn by the ocean can be rounder and have smoother shading like you'd find on a sphere. When painting a large scene though focus on areas of big shapes first and only start to worry about the specific details of the nearby rocks when the big picture looks solid. (I don't have my drawing tablet at the moment but I hope the draw over makes it a bit clearer)