If you open CC and then open the Help Menu and then About Menu you can open the data directory for CC. There is a fonts directory and you can just place a font in there. For Windows you can download a font and right click it and “Install for all Users”. and install a font into the system font folder. The system method of installing a font makes the font available to all applications on your computer while the placing of a font in the fonts folder of CC makes it available only to CC.
On windows installing a font is kind of a trick. The font is just copied to the system fonts folder there is no real magic of installing. Simply placing a font in the folder works. If the font comes compressed be sure you uncompressed it first before trying to install it.