To back up Kenny here, LPs don't really have "editable areas"
You would define the text area by the layout markers (graphics) or other pieces.
To make sure the fonts work well, you can define that in the CSS and then do this:
1. Create an LP in a Program as a Program Template.
2. define text and any tokens. Tokens will have the font you assign to it.
3. make the text areas do what you want.
4. save the LP.
5. clone this LP with the Program.
That way future LPs can be edited with text in the right spots with the right look and feel.