MacBook Air unable to write to external Harddisk I have a MacBook Air with mac OS Version 10.13.4 and I am not able to write to external disks formatted in format "Windows NT File System (NTFS)". 

It is definitely not an issue with the drive as I am able to write to the drive on Windows and Linux systems following these guidelines:


Plug the drive into a free USB slot. 


What are the corresponding instructions for a Mac? I am able to read from the external drive, but not to write. What are the precise, clear and direct instructions to be able to write to an external disk? (Disk, not sick)...
MacOS does not natively write to NTFS. Although it has write drivers installed, which can be activated via the command line following this set of instructions, this is complicated. Most users install a third-party driver such as OSX Fuse or Tuxera to write to NTFS. The only file systems that natively support read and write on MacOS, Windows, and Linux are ExFAT and FAT32.