Split Screen

Yes there is:

1-apple re hiring the people from the steve jobs era when macs were far better than today and the user didn't have to ask these questions because the features were there by default

2-I can program a mouse over. How difficult is it to do it in spaces? If the mouse is on the right window, it means I am going to do something there

This sloppiness is reflected in their products: complicated and full of useless features

No. One way or another your have to choose a window. If you don't like clicking, typing ^F4 should work.