If the drive(s) are not assigned a drive letter, partitioned or fomatted, CMD console or shell itself is not going to see the drive, that requires an app/utility with direct disk (BIOS) access like diskpart or other (which runs from CMD). Since you were previously running Windows 7 I presume you are still running in legacy BIOS mode with Secure Boot disabled (nothing changed in BIOS) rather than UEFI?
Are drives still being reported properly in BIOS setup view?