In PS, how does the following text darken?

Use the rectangular marquee tool to select a part of the word as the selection.

Ctrl+J, copy the selected part as a new layer.

On the new layer, select Image → Adjust → Replace Color.

Take the white in the font and replace it with a lower color (approximately light gray) in the color picker.

Select the Copy Stamp tool and select the sample as the current layer.

Hide the layer 1 and sample with the background of the background image.

Show the layer 1 and erase the changes.

Or use the "Stamp Imitation Tool" to erase all fonts, select the "Text Tool", set the same font as the original image, and select the desired color. Anyway, the font of the original picture has no special effects, and it doesn't take much effort to replace it.