I'll try and make it as easy as possible. This is the way I do it. Place your pointer/mouse onto the address of the relevant page in your browser. Right click and choose Copy. Go to your AB answer, right click again(anywhere) and choose Paste. Hey Presto.
This has been asked and answered lots of times before.
In what I'm about to type, this site may automatically insert
target="_blank"
so don't put that in yourself. Otherwise, to have the words "click here" link to google, copy and paste:
<a href="http://www.google.co.uk">CLICK HERE</a>
All you have to change is the site and the words "click here" (and remove the target = blank bit).
Tadaa!