Depending on the kind of browser that you're using, there are different ways to use the Cut, Copy, and Paste commands.
If you are a Mozilla user, please visit this link first:
Selecting Text
There are two ways to selecting or highlighting text.
One way is to place the cursor at the beginning of the text you wish to select, and hold-down the left mouse button. Now drag the cursor in the direction of the text you wish to select. To the right or left for single words or phrases, up or down for sentences and paragraphs. When all the text is selected, release the mouse button.
Another way is, with the cursor blinking at the start of the text you wish to select, press the "Shift" key and using the left, right, up, or down arrows select the text you wish to copy.
Copying Text
There are 3 different ways to "Copy" text.
You can click on "Edit" in the toolbar, and choose "Copy"
Or right click, and choose "Copy" from the menu.
Or use a keyboard shortcut by pressing the "Ctrl" key (Open Apple for Macs) + "C" key to Copy.
Pasting Text
To Paste the text, place the cursor where you want to place the text. These are the three methods you can use to "Paste" the text.
One method is to click on "Edit" in the toolbar, and choose "Paste"
Another way is to right click on the textarea, and choose "Paste" from the menu.
and finally, you can use the keyboard shortcut by pressing the "Ctrl" key + "V" key to Paste.
Now, test it out!
Paste here: