Reset iPhone 7 to factory settings directly from your phone
 

1. Go to your iPhone 7 Settings
2. Scroll down and tap General
3. Scroll all the way down and tap Reset
4. You’ll see a few options. You want to tap Erase All Content and Settings
5. Tap on Erase iPhone and tap Erase iPhone again (this is a security measure)
6. Enter your Apple ID — another security measure
7. Tap Erase
8. The phone will reboot and bring you to the initial setup screen

Reset iPhone 7 to factory settings using iTunes on your computer
 

1. Connect your iPhone 7 to your computer and launch iTunes
2. Allow iTunes to detect your iPhone 7. Once detected, click on the iPhone button
3. Under the Summary tab, click Restore iPhone
4. iTunes will now ask you to back up your iPhone 7. If this is something you haven’t done yet — this is a good time to do so
5. When you’re ready, click Restore and your iPhone 7 will be restored to its factory settings

Hard reset of iPhone 7 if you don’t know passcode or if it’s disabled
 

1. You’ll need the computer with iTunes and access to the internet
2. Connect iPhone 7 to computer
3. Start holding the Side button and the Volume down button together for around ten seconds until you see the recovery mode screen. Thereafter, you can release buttons
4. There is a pop-up window in iTunes asking if you want to restore or update your iPhone. Choose button Restore
5. Confirm that you want to restore iPhone to its factory settings by clicking Restore and Update
6. Wait until process of restoring is completed