To add a marquee, you must type the HTML code yourself for the marquee tag.
However, be advised that the marquee tag is obsolete and will cause your page to score low in search engines, fail standard tests and generally be considered non-professional.
Instead of marquee you should consider using javascript.
I never saw the marqee myself I know the html marquee language.
<marquee loop="5">place objects here</marquee>
Save as .html. The name of the application is marquee saves as marquee.html