Manager

Is there any way that at the start of a save you can become a real life manager or do you have to create a normal manager.

do you mean play as if you were the real Pep etc?

if so that is not possible 

You could create yourself as one of the real life managers when you start a new game but their history will not be with the character you create.

You will also need to use the Pre-Game editor to delete that manager so you don't have two of the same manager running around.