Changing your iPhone password is a great way to keep your device secure. You can do this by going to Settings, then tapping "Face ID & Passcode" or "Touch ID & Passcode" depending on your model. Enter your current passcode, then scroll down to select "Change Passcode." It's important to choose a strong, memorable passcode. Have you had any issues with passwords in the past, or is this part of routine security maintenance for you?