I want to upgrade my iPhone to 14.00

iOS 14 is no longer available -

• 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 17.4.1

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

olamidetaiwo wrote:

i went to upgrade my iphone to 14.00

If you have an iPhone 5s, 6, or 6 Plus, iOS 12 is the end of the line.

If you have an iPhone 6s, 6s Plus, SE (1st generation), 7, 7 Plus, 8, 8 Plus, X, XS, XS Max, XR, 11, 11 Pro, 11 Pro Max, or SE (2nd generation) that's running something earlier than iOS 14 now, you can upgrade that phone past iOS 14. (How far you can upgrade will depend on the specific iPhone model). But you won't be able to upgrade specifically to iOS 14.0. I'm guessing Apple pulled that upgrade once iOS 15 had been out a couple of months.

olamidetaiwo wrote:

i went to upgrade my iphone to 14.00

It is not possible to update to 14.00.

The actual version will depend on your device, but you have not provided that information.