Zero a hard drive in Linux

You might want to check the drive to see if it is still good in the first place. Go here first: Check hard drive for bad sectors
Unmount the drive: (if you haven't already)
sudo umount /dev/sdX*
Check with lsblk to confirm unmounting
Write zeros with progress:
sudo dd if=/dev/zero of=/dev/sdX bs=4M status=progress
status=progress displays transfer progress (e.g., bytes written).
Verify drive identifier:
Ensure sdX matches your drive to avoid data loss.