How do I download iOS 16 on iPhone 7?

iOS 15.8.4 is the end of the update road for the iPhone 7. No more updates will be available.

If you want to run iOS16, you need at minimum an iPhone 8, iPhone 8 Plus or iPhone X.

But, since you will be looking for a new phone, it would make more sense to buy a phone that is capable of iOS 18, like an iPhone 15 or iPhone 16.

The iPhone 7 originally ran iOS 10. You can update it to the latest release of iOS 15, but will never be able to update it to iOS 16 or higher.

You can’t get iOS 16 or higher on an iPhone 7. You need a new phone if you want iOS 16 or higher.

An iPhone 7 is incapable of running iOS 16. iOS 15 is the end of the line for your 9 year old iPhone.

If you have apps that need a higher version you need to replace your venerable device, as good as it was for its time. Take a look at the iPhone 16E, or iPhone SE (third generation), both of which can run iOS 18, if you have a limited budget.