How to update my iPhone X to iOS 17?

Not on an iPhone X. You need to have an iPhone XR or higher to run iOS 17.

Update your iPhone, iPad, or iPod touch

• If you have an iPhone 5S or 6/6plus, the highest you can update to is 12.5.7

• If you have an iPhone 6S through 7, or SE 1st generation, you can update to 15.8.2

• If you have an iPhone 8 or X, you can update to 16.7.7

• If you have an iPhone SE (2nd generation or later), or XR through 15, you can update to 17.5.1

Go to Settings > General > Software Update.

This link will show you how to update your iPhone, iPad, or iPod touch using WiFi -

Update your iPhone or iPad - Apple Support

This link will show you how to update using your computer -

Update iOS on iPhone - Apple Support

An iPhone 8, iPhone 8 Plus, or iPhone X isn't capable of 17 or above; they require an A12 or better CPU. For reference, the people on these boards are mostly other customers, not Apple employees.

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