How To Copy and Paste
Take your mouse, and place your cursor at the beginning of the text in the box below, then click and hold the left mouse button, while pulling your mouse over the text. This should highlight the text.

Now release the left mouse button. Now, with the cursor over the highlighted text, right click the mouse for options, and select "copy". Now over the empty box below, right click your mouse again, and select "paste" and you will have copied and pasted the text.

Cut and paste is the same as above, except you choose 'cut', instead of 'copy'.

Shortcuts
To Highlight: Press 'Ctrl' + 'A'.
To Copy: Highlight an area, as shown above, then hold 'Ctrl' + 'C'
(For Mac users 'Apple' + 'C').
To Paste: Click your mouse where you want the text pasted, and then press 'Ctrl' + 'V'
(For Mac users 'Apple' + 'S'. )

The ability to cut, copy, and paste is a function of your operating system. Some programs will disable the mouse menu but you can still copy and paste using the shortcuts. You should also be aware that some programs use different clipboards, so it is not always possible to copy from one program to another without changing the clipboard. But operating within the same program should be relatively simple.