Understood. Please follow these steps to perform a factory reset:
A master reset deletes all media and data and resets all settings. ...
If you see the Apple logo or a red or blue screen during startup, follow the next steps: You will need to connect your device to a computer and open iTunes. If you don't have a computer, try to borrow one, or go to an Apple Store:
1- Press and hold the Side button until the power-off slider appears. Drag the slider to turn off your device. Connect your device to your computer while holding the Home button. Keep holding the Home button until you see the recovery-mode screen.
2- When you get the option to restore or update, choose Update. iTunes will try to reinstall iOS without erasing your data.
3- iTunes will download the software for your device. If it takes more than 15 minutes, your device will exit recovery mode and you'll need to repeat steps 1 and 2.