Have you noticed how YouTubers rattle on with their video explanation of post-processing, telling you to do this or that with your sliders, but never actually explain their choices or the effects of the sliders?
The sliders shown here are likely to be found whatever photo editing software you chose.
Below are some sample photos. The original and modified images with the settings used to improve the look of the pictures.
The best image format is DNG or RAW, because these files have the maximum pixel info to work with. JPG discards information to enable compression and small file size and there is no way to recover it.
If there is an AUTO button, I suggest you use it and adjust from there.
The Bay Original was taken late evening. The colours are good but can stand brightening.
TEMPERATURE colour and TINT seem ideal.
EXPOSURE is increased slightly to boost brightness overall.
CONTRAST is increased slightly so there is a greater range for a given tone. This also makes the edges between tones more distinct. Looks sharper but not the same as sharpening. Because EXPOSURE was brightened, the darkening from CONTRAST has been eliminated.
HIGHLIGHTS are reduced and makes clouds more distinct. A good slider for creating moody clouds.
SHADOWS caused here by low sun angle need lightening. CONTRAST will make them darker, so this compensates.
WHITES often need to be lowered, especially in the bright sky with clouds scenes. It also helps if you have any detail left in the region around the sun.
BLACKS Can stand a little darkening. The blackest regions can be darkened if the scene is bright.
TEXTURE CLARITY and DEHAZE are quite different effects, but exhibit some overlapping features.
TEXTURE tends to unsharpen or defocus towards the left, sharpen and strengthens tones, a bit like CONTRAST. Use sparingly if at all.
CLARITY strengthens the edges of tones (to the right). This gives the illusion of greater sharpness of detail. It doesn't actually sharpen.
DEHAZE strengthens tones (to the right) so they punch through moisture haze. Similar to CONTRAST and TEXTURE. It also increases noise effects and oversaturates tones.
VIBRANCE makes weak tones stronger and is great for avoiding lobster coloured skin tones. This is the preferred slider for adjusting colour, NOT SATURATION.
SATURATION makes Reds redder, Green greener etc. Avoid using it if you can.

Volcano Original is dark and featureless. Increasing EXPOSURE just lightens everything. We need to increase the differences in the various dark shades so they stand out and give the picture some life. TEMPERATURE needed warming. TINT needed bosting in the Magenta region, to bring out the purple effect of the weathered lava.
It is a dark scene that is underexposed, so lighten the exposure.
CONTRAST needs bosting to make the different shades stand out and look more distinct.
HIGHLIGHTS need reducing to boost the clouds and blue of the sky.
SHADOWS need a lot of boosting to lighten the mid-tones.
WHITES need a lift and will also lighten this scene.
BLACKS are darkened to add to the range of tones.
No TEXTURE change.
CLARITY will make the edges of tones look better defined.
DEHAZE boosts the blue of the sky and reduces the strong moisture haze from the sea and steaming lava.
The colours are generally muted, so boosting them with VIBRANCE and making them more colourful with SATURATION is advantageous here.

I hope this might help beginners try to improve their photos by experimenting with these simple, basic tools.

Nice examples of editing.

Great info, what is that editor you are using?

Actually, the editor isn't important, in as much as those controls are found on most editors. However it is Photoshop CC. Just make sure you work with DNG or referred to as RAW format files.
I was planning on other tips, depending on what people want and response to this post.
If you have questions, please ask.

Very informative!

Does anyone want more of these photography tips?
I won't know unless you tell me.