The disappearing window and other, annoying 'improvements'

The latest version of Macos 14.4.1 has yet another annoying 'improvement' that clicking on the active window moves/reduces it to to the side (god know what you call this!). How do I disable this really infuriating 'improvement'? I've searched through the so-called help to no avail.

Associated with this the failure for Show and Hide to work in lots of applications as well as the other 'improvement' Apple have made to moving files around on the Desktop. It used to be that I'd click and hold the mouse (with an option to hold the Option key to copy it) but now I'm forced to hold either the Option of Command key. It's yet another useless 'improvement'.

What used to be an intuitive interface is now one awful dog and I've been using Macs since 1985.