As @
Mike Dee said, you'll need to look for a device that WILL support Disney+. Even if you could get that device to update to a version of Android supported by Disney+ it probably won't last long as the service develops and the app updates.
That's a device I've never seen asked about here, likely a no-name device that could be had for super cheap when new but suffered from the lack of support all devices like that see. An additional side effect of the non-mainstream device is that it's not likely to be one that enterprising individuals will develop a version of the updated OS for.
While I understand budget may be a concern, I wouldn't buy a lower-end tablet running anything earlier than Pie (Android 9) right now.
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