How to update my iPhone?

Start here: Update your iPhone, iPad, or iPod touch - Apple Support

1. Go to Settings > General, then tap Software Update.
2. If you see two software update options available, choose the one you want to install.

Tap Install Now. If you see Download and Install instead, tap it to download the update, enter your passcode, then tap Install Now. If you don't know your passcode, find out what to do.

You may see that your device is up to date and that there's an upgrade available. For example, even if your device is up to date with the latest version of iOS 14, there may be an option to upgrade to iOS 15. You may want to upgrade iOS when you pair an accessory with iPhone.

[Edited by Moderator]