A new text layer is created when you insert text into a graphic.
Clicking on the photo will position in a curser and you can now
select the font options. The available fonts in your system will
be available as they are in all the other text applications you
work with.
Once a text layer has been made you can move it around with the
move tool and change it like you would any other layer. You can
even set the transparency options if you wish. The move tool is
Once you have created your text on a photo you are best not to reduce
the size of the photo because I find this degrades the text. You
are best to resize the photo before you place the text on it and
then save the final result.