Broken home button and phone locked on "press home to upgrade"

Good evening. I have a old iPhone 8 plus that I want to give to my son. I cleared it out and backed up my sons phone to the 8 plus and it now says "Press home to upgrade". The problem is the home button doesn't work and hasn't in a long time and when I go to do a hard reset (volume and sleep button) the "turn off" slide bar will not show up. I tried to get to it on iTunes but it has a password on the phone now and iTunes won't do anything until I put in the password on the phone. Is there anyway to fix this or am I S.O.L? Pease help if anyone can.