linux – image of raspberry copy to another pi?

I have a Raspbery Pi with a damaged microSD card (it crashed as if it were damaged, as in several pieces, do not ask me what the user did, but it happened …).

I have a copy of all the contents of the Pi (I made a copy of the complete partition a while ago with the cp command in Linux).
The microSD card re-added the correct version of Raspbian as before; it's an empty Pi installation now.

Now I want the old backup in the new Pi, so I mounted the partition and ran cp / home / my-pc / pi-backup / mnt, but that does not work. Someone who can help?