What is generally adjusted in the later stage of photography? How to improve the density?

1. The color scale must be adjusted, that is, the brightness is required to be correct.

2. Generally, it is necessary to adjust the color, which is a matter of white balance.

3. In order to look good, the saturation is generally increased.

It may become soft or sharp.

As for other aspects, it is advanced.

If the density increases? I don't know what to say.