Here are the steps to hard reset the Device:

Back up your device
Make sure to back up your device so that you can restore your data later.

Tap Settings > General > Transfer or Reset [Device]
Tap Erase All Content and Settings.

Erase All Content and Settings from your iPhone
If asked, enter your passcode or Apple ID password
Forgot your passcode or Apple ID password?

Confirm that you want to erase your device
If you have an eSIM, you can choose to erase your eSIM or keep it. If you erase your eSIM, you need to contact your carrier to reactivate your cellular plan.

Wait for your device to erase
It might take a few minutes to completely erase your data.