HTML does not honor line breaks, so adding "\n" to a string won't work. You'd have to insert a line-breaking HTML tag such as "<br/>" or "<p/>" in place of the newline character,
However, that won't work either unless you turn off escaping on your outputText tag, since it will otherwise just print those tags on the screen.
It's really best not to attempt to do page formatting in backing beans. Doing so breaks the separation of concerns that defines MVC by putting View functionality (line formatting) into the Model (backing bean). A cleaner approach is to use a suitable JSF definition - for example a 1-column panelGrid or a dataTable.
An IDE is no substitute for an Intelligent Developer.