You are probably trying to put an RTF (Rich Text Format) editor on your page. You'll need that to be added to an element page in order to use RTF text.
Go to management mode: "Manage Site." Then on the toolbar titled "Page Tools," click "Add Element," --
Once you have added your RTF editor, you need to select "Page Layout" and position your editor location where you want it on your page.
Here's what the layout looks like on one of our sites (http://www.ardent-webs.spruz.com/home.htm):
The RTF editor is just under the navigation bar in the very top global area. Next, you need to click on the RTF editor and drag it to to the place on the page where you want it. Be sure to click on 'Save Element Order' at page bottom. Then just click on 'Edit' and enter your text.
And you're ready to go with RTF text.
