How can I update my iPhone 7 Plus to latest iOS

If your iPhone 7 is currently at iOS 14 as your tagline states, you should be able to update to iOS 16 by selecting settings > general > software update. If your phone is eligible for an update, you will be prompted to do so.

If your phone is already at iOS 16, then, as Niel said, you will not be able to update. That phone is too old and does not have the required hardware needed to update higher than 16.

An iPhone 6s, iPhone 6s Plus, iPhone 7, iPhone 7 Plus, or iPhone SE 1 isn't capable of 16 or above; they require an A11 or better CPU. To install 15.8.3, use a computer or the Software Update function in Settings.

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If your iPhone 7 is currently at iOS 14 as your tagline states, you should be able to update to iOS 16

The iPhone 7 can only go as far as iOS 15.8.3. It does not have the processing power to run iOS 16.

The highest version for an iPhone 7 Plus is 15, not 16.

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