how can i make a copy of the OEM ?

so what is possible ? my windows 8 was pre- installed , how can i make a copy of the OEM ?
AND

Then i ran powershell DSIM after SFC scan , when it (Sfc COULD NOT fix some windows files )
first ran
this 1)"Repair-WindowsImage -Online -CheckHealth"

path :
online : False
image health state : repairable
restart needed :false

2)Repair-WindowsImage -Online -ScanHealth

same as above

3)Repair-WindowsImage -Online -RestoreHealth

it said to reboot to let updates be installed

and all the update where installed successfully


then next is new CBS LOG

You can do an image backup to an external USB hard drive using a program like Macrium Reflect Free. You can buy a 1TB external USB hard drive for around $60 US.

Don't understand what the 2nd part of your post is about, can you explain please?