This really should be a standard feature, everyone seems to have their own window manager for Mac desktops. I use an app called Window Mover that's so old the developer and dmg can't be found anywhere online, but it still works flawlessly on Monterey! Much more minimal than some of the populat apps so I keep the package handy. Using other Macs I'm struck by how clumsy it is not to have global window drag to move or resize. Fn is my favorite modifier since it so rarely interacts with the cursor (unlike other mod keys when using eg Photoshop).