Before Starting the update, make sure your device is plugged into your computer
and that your computer is connected to the internet
If you're using a Mac with macOS Catalina or later,
open the finder.
If you're using a Mac with macOS Mojave or earlier
or a Windows computer open iTunes
You might receive a notification when a new update is available
Which you can click to start the update process
Otherwise, locate your device in the sidebar
and make sure you're in the General tab
Next, click update
Then click update again and follow the prompts
When the update is complete your iPhone will restart.
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