You lose all the prior information. I see you may not still be ready to tackle this work since your note about ISO at https://www.cnet.com/forums/discussions/cloning-a-hd-to-ssd-with-easeus-todo-backup/#post-2643b379-cfb8-4c62-8927-3a9bf0193b79 says you are still learning.
You also were not given a good answer by Apricorn so that's annoying to me since I use that system and have to disagree with their answer.
At this point you may have to pay someone to do the work.
I am sure that you are tired of hearing about my problems....
But can anyone explain to me:
Why will my new computer run my old computer's HD (in a usb-box adapter). I boot the new computer with the usb-HD attached and it boots off the old HD. It calls the HD the "C" drive and I have total access to all the programs just like I did when the drive was in my (now dead computer).
BUT when I clone the usb-HD to my internal NEW ssd , on my new computer, and, then shutdown the computer and disconnect the usb-HD and try to boot the computer I just get a display on the monitor "operating system is missing". I am a novice and I really cannot wrap my mind around this situation. I have been "messing" with computers since the early '80's.
Any comments would be greatly appreciated.