You need to install the fonts.
The most accurate way is to go to the fonts folder (can be access via the control panel, if not try windows/fonts) go to File> Install New Fonts, and browse for the new font(s) you want to install.
Once they're installed, you'll need to close and re-open photoshop (if you have it open). Then it will recognize the new fonts, load them, and be ready for use.
peace