Hi how can update my iPhone 6s

Bk ~ Learn how to update your iPhone, iPad, or iPod touch to the latest version of iOS or iPadOS:

Update your iPhone, iPad, or iPod touch

If your iPhone, iPad or iPod touch won’t update

Updating iOS: common issues and solutions - Apple Community

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

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What iOS version is currently running on it? (check: Settings>General>About>Software Version).

Use a computer or the Software Update function in Settings. If you encounter a specific issue, describe it in this thread.

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