iPhone 16 Pro Max update stuck, keyboard glitching, and can't power off

Setting up my new iPhone 16 Pro Max using my other iPhone. Wanted to update the software on the new phone. I said yes. After some time the update froze. When I try to swipe up the the keyboard pad appears and disappears in an instant. Have performed multiple forced restarts and same issue. Unable to power down the iPhone as well. Help!!

[Re-Titled by Moderator]