Thanks a lot for trying
Notezilla and for your appreciation.
Double click inside the sticky note to edit the note and then right click inside the sticky note to find out what editor you are using.
If you are using the markdown editor then you will seen and option called Formattting in the menu. Just click on it to see the format toolbar at the bottom.
If you are using the standard editor then you will directly see options to change the font, size etc in the menu.
When you change the default font from Preferences window of
Notezilla , the newly set font is applied to only new notes. For existing notes if you are using the markdown editor then the new font will be applied once you edit an existing note. If you are using standard editor the you will have to explicitly go to the existing notes and change the fonts.