Can't open file on MacOS for reading/writing

• First, Mount NTFS volumes as Read/Write

$ sudo umount /Volumes/NTFS
$ sudo mount -t ntfs -o rw,auto,nobrowse /dev/disk3s1 /Volumes/NTFS

Reference: https://mounty.app/

• Second, if you can't open a file on MacOS because “this item is used by Mac OS X”, then

SetFile -c "" -t "" path/to/file

Reference:

https://apple.stackexchange.com/questions/136157/mov-file-in-external-hd-greyed-out-and-wont-open-this-item-is-used-by-mac-o