Chances are that you already have the text for your page typed, most likely in Microsoft Word. When pasting into the Edit Content Window, all of the formatting will be stripped. If, however, you drag and drop the text, the formatting will be preserved.
The styles available for you to use when formatting your pages are dependent on the Template. These are predefined styles and cannot be changed, i.e. use a different color, font or size.
Line breaks can be inserted by holding down the Shift key and pressing the Return (Mac) or Enter (Windows) key on the keyboard.