Mac not detecting my passport 2TB

WD External and Portable SSD External SSD for macOS
1

I am using a 12" MacBook and I was unable to transfer data from my mac to the hard disk, so I tried to change its format from NTFS to mac OS extended by using the ‘erase’ button in disk utilities. But in the process of doing so an error occurred and from then onwards my mac is not detecting the hard disk.

  1. Now can I protect the data on my hard disk?
  2. And how to format it so it can be used for both mac and windows?
2

You first need a working file system on your external drive to perform any action. Try formatting your ex-hdd using the terminal. Here is a guide How To Format An External Drive In OS X

You can use ex-fat on your EHDD so that it can work on Mac & Windows.