A question about toggle split

I wonder if i can do this.

When I use toggle split, can I on the top window have corkboard and when I mark one card I want this cards text to show up on the lower window. So I can write inside the card I marked at the top window, when I mark another card in the top window the new cards inside text will show up in the lower window.

Can I do this today?

Hope you understand my question

Not a problem! You see that little button at the bottom of the Corkboard display that looks like two opposing arrows? Click that, and when it is blue that activates automatic selection mode. Now whenever you click on something (and this works in Outliner, too), it will show up in the other split – even opening a split for you if necessary.