Need to completely reset an iPhone 7
I was given an iPhone 7 and it was the woman's husband's phone but she didn't know his password to his apple ID account so i cannot turn "find my iphone" off to reset it. Is there anything i can do to completely restore it on my own at home or do i have to go to an Apple store to have it done and how much does it cost to do so?
Thanks in advance.
iPhone 7