It's recovery mode. I'll post the link to the support page, it will guide you on how to do it just make sure to follow for your specific phone as each phone is different.

https://support.apple.com/en-us/HT201263#:~:text=1%20Make%20sure%20that%20your%20Mac%20is%20up,with%20these%20steps%2C%20but%20don%27t%20...%20See%20More