I reset my phone but won’t load
So I’m wanting to hand down my iPhone 8 to my little cousin for his birthday, and when I erased all data to reset the phone, it didn’t load. Like when you erase all data it brings you to a loading screen. Yea it’s stuck on the loading screen and has not made any progress and it’s been about 3 hours. I can not turn off the screen or restart my phone. Please tell me what I should do please
iPhone 8