1. Open the file, copy the layer (bottom protection), and adjust the automatic contrast.

2. According to the needs of each picture, adjust the color and curve (Ctrl+m) and confirm, then bring up the curve window to continue the curve, adjust the RGB, red, green and blue channels according to the range of picture demonstration, and then liquefy the unnatural parts of the characters in a proper amount.

3. Execute "Image/Adjustment/Optional Color" and adjust the color according to the needs of the screen.

If the above methods can't solve the problem, please try:

Brightness and contrast: In the image adjustment toolbar, you can brighten the face.

Brightening: In the shortcut toolbar on the left, after selection, adjust the brush size to a suitable range and smear the face of the person.

Layer Covering: Create a new layer, choose the brush tool, paint the range of the face of the person in red (light pink or similar in flesh color), remove the part that you don't want to cover with the eraser, and then adjust the transparency of the layer until the face of the person achieves the desired natural effect.

Repair tool: In the shortcut toolbar on the left, you can modify details and dark parts.

Rubbing: copy the layer, hide the original layer, then select Gaussian blur in the filter blur effect, set the blur degree in the pop-up dialog box, which is generally 1 (it seems to be), and finally choose the history brush tool to smear the face of the person, which can beautify the skin.

Imitation stamp: in the shortcut toolbar on the left, press and hold Alt key after selection, click once in the part with lighter skin color, and then click in the part with darker skin color to copy the lighter skin color and cover the darker color.