What mode of colors is used usually in photoshop?

As you ask for Photoshop is better to yous the standart : RGB color8bit on Resolution72.

If you need for print materials go for : CMYK color sheme on Resolution300 /600

But for printing just use Adobe Illustrator is easy to scale your project

For print media... should be CMYK mode with300 dpi. Web72 dpi with RGB mode.

If you know beforehand that your work is going to be sent to a commercial printer, then it’s best to start your document in CMYK mode. Otherwise it’s safe to always work in RGB for almost any other project.