What security options are available on my iPhone?

You can use Face ID or a Passcode to secure your device. Face ID will require you to capture a scan of your face, which can then be used to unlock the screen, use Apple Pay, and verify purchases in iTunes and the App Store. Your passcode can be used to unlock your device’s screen.

Once you have signed in with your Apple ID, "Find My" iPhone security will automatically be enabled. This feature allows you to track down and locate your iPhone if it's ever lost or stolen, and can improve the odds of finding your device even when it is not connected to the internet.