Copy terminal result from one window to another

Ctrl + Shift + c --> Copy

Ctrl + Shift + v --> paste

In terminal... Go to Edit > Keyboard Shortcuts... and this window opens...

you highlight the text (or double left click it) you want to copy with the mouse and Ctrl+Shift+C to copy and Ctrl+Shift+V to paste. Also you can highlight text with the mouse and use the middle mouse key/scroll wheel to paste.

Another solution: you do not need to use keyboard shortcuts at all!

Just mark what you want with the left mouse button (for example, double clicking a word), and paste it by clicking the middle mouse button in the other terminal. This is the "old style" X clipboard.