Comic Strip Factory™ allows the creation of text balloons in comics. That means that to use that feature, you need some good comic fonts. Please note that Comic Sans is not a good comic font and should not be used unless you want to be mocked mercilessly. Fortunately, there are a bunch of free comic fonts available, and the best source I have found for them is Blambot Comic Fonts and Lettering. Blambot sells a lot of their fonts, but they give many of them away free for independent comics use or non-commercial use. Look for the fonts in their library with this icon: . A good, general purpose font for dialogue is Digital Strip 2, but you may find others that suit your personal style better.
As a tip, to make your collection of comic fonts easier to find, open up the Fonts panel with the Format->Font->Show Fonts command and click the + button to add a new Collection, name the collection Comic, and drag all of your comic fonts into it.