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').