Mirror Image

Ok just bought this passport to do a complete system back up (Mirror Image) of my internal hard drive. I do not need just files done as I need to put my computer into the shop to be worked on and the last time they worked on it i got back a system with all my stuff gone. ie just as if i had just bought it updates took forever never mind all the reinstalls. Any how I’m off topic. I am wanting to copy everything on my internal hd and just cant figure it out can anyone help me?

As far as I know, WD’s software for external drives won’t do that.