In page design view, if you use the text tool (marked 'A') to draw a small box, you should see a dialogue box open, marked 'Text properties'.
At the bottom left of this box there'll be a button marked 'Link'. Click this, and you'll be able to specify an external link from the drop down menu, and you can type in the url of the page you want to link to. There are plenty of linking options, and you should spend some time exploring the possibilities - it's far too comprehensive a subject to go into at any length here.
Once you've created your link, click on the HTML source button, and you'll see the code that NOF has used to create the link.
One way to learn how to use any software application is to explore, and see what happens when you change something. You can always revert to the previous state if you make a mistake, or if something turns out differently to what you expected. Be bold, and try all the buttons - soon you won't feel so lost.