I have been gifted an old iPad Air. I cannot get the original log in details. Can I unlock it somehow?

The iPad in question is an iPad Air, about 4 year’s old. The owner bought it new but didn’t really learn how to use it. He forgot his Apple ID and log in details. Find my Iphone was enabled. He took it to an Apple store a couple of years ago but they correctly told him they could not open it. He has now bought a non Apple tablet, vowing never to buy Apple again. It has sat in his loft ever since. He is now moving and my wife has been helping him with his house clearance. The virtually unused iPad Air has been offered to my wife. I am a big apple fan, iPad Pro 10.5, IPhone X and Mac Pro. I would like to unlock the iPad Air for my wife to use. Is this possible? How do I do it? Many thanks.