Buy and download an app. Tap Get (if the app is free) or the price. If you see instead of Get or the price, you’ve already purchased this app before. Tap to download it again for free. If required, authenticate with Face ID, Touch ID, or your passcode to complete your purchase. You can find the app in the Recently Added category in App Library.
That is a 3rd gen. It doesn't run apps, just preset content sent via server. Providers have also started to drop support. You would need an Apple TV HD (4th gen) or Apple TV 4K in order to have access to the app store.
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