There isn’t one single “correct” setting for distant landscapes. The result depends on several factors, including your camera, lens, focal length, aperture, composition, and especially atmospheric haze.

A big point here is that haze over long distances is often caused by the air itself, not just bad focus or camera settings. In those cases, camera settings alone may not fully fix it. You can improve the image somewhat in post-processing with a dehaze/haze-removal tool; one community answer specifically mentioned Affinity Photo’s Haze Removal filter, and similar tools exist in other editors. These can help, but they are not miracle cures.

For camera technique, the best approach is to learn how aperture, focal length, and depth of field affect the look of the scene, then choose settings based on the photo you want to make. In other words, there is no universal setup—your preferred look matters, and understanding those variables is key.