Go to Theme customization -> Typography

You can choose custom font families and settings from Google Fonts list.
If you experience issues with accented letters or non-English characters, make sure your language is supported by the font you choose on http://fonts.google.com.

NOTE: If the selected font doesn’t look nice, you can select a different text-rendering property to fine-tune optimization by suggesting to the browser how it should render text on the screen.

Click Publish to save changes.