You can purchase or rent the movie from the iTunes Store or Apple TV app. Downloads are DRM-protected and viewable on Apple devices.
When you type this keyword into a search engine, you may find dozens of websites offering free downloads. However, these sites are typically:
If you want a local digital copy, follow this method using ZEE5 (most reliable):
Note: Legally downloaded files are encrypted and can’t be shared or copied to unauthorized devices. That’s how copyright protection works.