How To "Manually" Restore Windows 10 System Image

I posted this same question and have not seen any replies, so don't know if I am posting correctly, so will try again.

I have a Dell Inspiron desktop with windows 10.

In case my system gets so corrupted I can't get to the Windows Sign In screen, I want to be able to restore my system image.

I have created a system image on an external hard drive using the Windows Control Panel.  I also created a System Repair DVD.

I powered the system down, connected the hard disk containing the system image, and inserted the Repair DVD.

I then powered on and pressed the F12 key until I got a "primitive" Dell screen.   I am trying to figure out which options from this screen that will allow me to restore the system image, or get to a Windows screen that will allow me to do this.

Please help.   thank  you