To link to a different page, simply highlight, using your mouse, the text you want linked.  Be careful with extra spaces so that only the words are highlighted and not the preceding or trailing space.

Once you have the text highlighted, click the button in the toolbar that looks like a chain (not the broken chain - the broken chain is used to remove a link).

When the popup comes up, enter the name of the page you would like to link to.

Save your changes and your link will be set.

This one is a bit trickier...

What you'll want to do here is make sure you have everything all set and then follow these directions:

1. Do this first
2. Do this second

Warning! Always follow these instructions!