disabled iPad needing unlocked.

Okay so my brother was given an iPad from school to do homework from home during this shutdown, and him being a 7 year old made a super LONG and tedious password, and forgot it as well as disabling his device. and I've tried everything I've read as well as watched on youtube.

When I try to connect it to my Mac book air13 to connect to my iTunes and unlock it it tells me I need to use the passcode on the iPad to connect, and I've been going in circles. I'm really NOT trying to pay loads of money to get it unlocked, seeing as I been laid off due to this virus shut down so PLEASE someone help!!! 😂😭