My iPad is 8th gen and won’t update to the new iOS, tried plugging in into a Mac but it still doesn’t work

Trying to update my iPad it only says “verifying update” for ages until it says “can’t install update”. Then if a do it from a Mac it only says “couldn’t find unit. After I’ve tried for ages… do I need a new ipad? Can’t use half of the apps on it now because it won’t update.