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An Apple TV+ subscription gives you access the the Apple TV+ catalog (note the Plus) (Apple Originals), not other content in the Apple TV app. That other content will have to be paid for separately.

With the Apple TV app on your smart TV or third party streaming device, you can access:

• iTunes Store movies and TV shows (buy or rent);
• Apple TV+ channel featuring Apple Originals, by subscription;
• other premium Apple TV app Channels, each by separate subscription.

List of Apple TV+ original programming (series/episodic) - Wikipedia

List of Apple TV+ original films - Wikipedia

• For movies from the iTunes Store movies catalog, there is no subscription option. These are buy or rent.
• For select premium Apple TV app Channel subscription, see the channel overview in the Watch Now tab of the Apple TV app. For the US, Macworld list the channels on their webpage as well. (It is different for other countries.)
• For content from e.g. Disney, try what a Disney+ subscription may offer on your device. You would watch that in a separate content provider app.

On Android TV devices, you can't purchase content or subscribe through the Apple TV app at this time. You can buy, rent, or subscribe on another supported device and then watch in the Apple TV app on your Android TV device. [1]