I don’t know how NTFS does it, but on FAT filesystems the directory table contains the filename along with all the other file metadata (access rights, creation date, size, etc). Only the list of sectors containing the actual data is separate. That means that you can’t have two filenames for the same file on FAT filesystems.
If you want to learn more about this, the data structure UNIX filesystems use, and FAT filesystems lack is called inode.
I don’t know how NTFS does it, but on FAT filesystems the directory table contains the filename along with all the other file metadata (access rights, creation date, size, etc). Only the list of sectors containing the actual data is separate. That means that you can’t have two filenames for the same file on FAT filesystems.
If you want to learn more about this, the data structure UNIX filesystems use, and FAT filesystems lack is called inode.