Deleting files from previous Time Machine drive

Steven Culberson wrote:

Cannot delete folder, "Needs to be downloaded". ??

Erase and reformat a storage device in Disk Utility on Mac

Erase and reformat a storage device in Disk Utility on Mac - Apple Support

the most straightforward way to remove ALL files from a backup drive is to completely ERASE the drive, by its immutable manufacturer-given Device-name. (not just by User-assigned Volume-name).

Selectively removing a file here and there with the Finder will corrupt your Backup Set and leave it unusable.