NTFS is a more recent technology compared to share permissions. NTFS is the short form of the New Technology File System. NTFS permissions can only work for local users of the machine. It is a function that helps prevent unauthorized access to certain applications and also to stop the execution of those applications.
In the case of share permissions, this function comes in handy to help prevent an individual working remotely on the machine from unauthorized executions of applications. With the explanation above, it is very obvious that the location of the person accessing the computer is the major difference between the two.
If an operating system has NTFS, all the folders and files in it will automatically have the NTFS permissions, whereas you will need to share your files and folders before the share permissions can work. However, it is obvious both NTFS and share permissions are just security functions to protect your computer.