Having a correctly calibrated monitor is the most important factor when you want to prepare images for printing. Without a calibrated monitor you won’t know what the image actually looks like.
Calibrating the monitor means to balance and correct its colors, typically done by using a spectrometer and calibration software. This is something everyone should do even if they don’t plan on printing an image. If the colors of your monitor are off, it means that all your images look different on other devices.
There are various tools out there that you can use to calibrate the monitor. One way to do this is calibrating in windows follow the link for instructions
Screen Calibration in Windows
and Calibration in macOS macOS Screen Calibration.