You can select from a number of pre-set fonts, or choose your own by replacing/substituting your preference in the HTML,
though unless someone has the font you have chosen on their device, they will not see it, but only the default...
I have downloaded hundreds and hundreds of extra fonts to use on my panels, but not all are suitable due to legibility or
sharpness concerns, and of course they do show up for everybody when I use them on a panel, because it is part of an image.