How do i get IOS 14.0?

If you don't have it, there's no means to get it. Anything older than an iPhone 6s/6s Plus will be maxed out at iOS 12 at the highest, and anything newer is currently OK for iOS 15.

If you're using an iPhone 6s or newer, install 15.6 from a computer or through the Software Update function in Settings. Older models aren't capable of it.

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