Here's how to use the font selection panel:
Click on the text-field you wish to edit.
Change text-field setting from the Typography panel on the left
If you're looking to add a new font - please make sure your service plan allows it - or contact us via chat.
Tip: to change the font on all of your scenes:
Click Manage Scenes - bottom right
Click the Typography panel on the right
Select the element you wish to edit (ie. headlines)
Select your font
Optional - you can select the size, alignment and format too.