Copying and pasting from CBX is as simple as dragging your cursor over the text/field you want to copy, then moving to the destination and either using CTRL+V (your keyboard's shortcut to paste) or right-clicking and selecting Paste from the option menu. 

Additionally in Edge, if you highlight the text/field you would like to copy and hover, the Copy option will appear and allow you to copy. Follow the above instructions to paste to your destination. 

If attempting to paste text from an outside source into CBX, select the field and use CTRL+V to paste the text you've copied into that field.