If you already have the html code for inserting an image then you just
need to make sure that the image is in the same folder that your game
is. If it is than the image should work.
To change the font you need to make a new passage, put the tag as
"stylesheet" (without the quotes), and in that passage you can use
code like "div { font-family:papyrus; }" to change the font type, or
"a { color: maroon !important } " to change the font color (again,
without the quotes). Of course you can put in your preferred font or
link color.
I'm not sure about the title thing. my only advice would be to use
Sugarcane if you don't want the reader to see the titles, but there
should be a way to get rid of them in Jonah.