It contains 250 images of real life youth footballers from around the globe, of all ethnicity's. There reputations are all low enough where its unlikely you will come across the same image if you already have a facepack installed.
The idea of the pack is to pick individual images for regens you have purchased or maybe just want to add some real faces to the best players around the world to make your game feel a bit more real as you advance into the future.
How to use this packExtract the contents of the downloaded .zip file using a free tool such as 7-zip (for Windows) or The Unarchiver (for Mac).
Move the folder to the following directory path:
Documents > Sports Interactive > Football Manager 2023 > graphics > faces >
Create a config file with any text editor or with fmXML and assign the face(s) of your choice to the player(s) you want.
Then go to the preferences area in-game to clear cache and reload skin.
This is the link to a youtube video easily explaining how to add individual images to players in the game, if you are unsure on how to do so. It was made for FM21, but it's the same process.