If you want to use fonts that are not included in PowerPoint, you can get more font sets from third-party vendors.
When you download and install these fonts (from Windows) you can then use them in any of your software applications.
Download third-party fonts at your own risk.
There are many legitimate sites where you can purchase fonts, however some vendors don’t allow you to embed them. This can be a problem if you’re planning to send your presentation to others who don’t have these fonts installed. They won’t see the fonts you’ve carefully selected. Instead, they’ll see a substitute font chosen from among those they have on their computer.
While there are free fonts sites on the web, some fonts are incomplete sets, and others might conflict with fonts you already have on your computer.