How to unlock my iPhone?

Unlock how? There are a number of locks that can be on an iPhone. See this.

• Device disabled message or forgot passcode —>If you forgot the passcode for your iPhone, iPad, or iPod touch, or your device is disabled - Apple Support
• SIM locked to a carrier: Contact the carrier it is locked to and ask about their unlocking policy—>How to unlock your iPhone for use with a different carrier - Apple Support
• SIM PIN lock—>Contact your carrier for the SIM PUK code
• Apple ID locked—>If your Apple ID is locked or disabled - Apple Support
• Device Activation Locked—>Turn off Activation Lock - Apple Support

How is it locked exactly? Seems to be accessible and not actually locked since you can get to the About screen.

If you mean locked to a cellular service provider, then only the service provider it is locked to can unlock it. See here: link-> How to unlock your iPhone for use with a different carrier - Apple Support

Otherwise you will need to explain how it is locked exactly.

Hello there !

No one can open your phone for you here, we are just users just like you. We can only give you the steps so that you can fix your problem. Can you give us more details about your problem and what the picture has to do with your problem?