I want to update my iPhone 6s from 12 version to above 14 how can I do it ??

If you are unable to update your phone higher than 12.5.6, then you don't have an iPhone 6S. You have an iPhone 6 or 6 plus.

Go to Settings > General > About and see what model you have.

• If you have an iPhone 5S or 6/6plus, the highest you can update to is 12.5.6

• If you have an iPhone 6S through 7, you can update to 15.7.2

• If you have an iPhone 8 or higher, you can update to 16.2

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

abhinay ~ See if it's possible here:

Settings > General > About > Model Name

iOS 16 and iPadOS are compatible with these devices

...Found by searching Apple's Knowledge Base.

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