What the author says it does
Pick a font from a dropdown and watch your site change live. When you’re happy, click Publish.
The preview updates on your own content as you browse, so you can try as many fonts as you like before anything goes live. You never need to edit theme files or write CSS.
Fonts Plugin is the #1 fonts plugin for WordPress: 200,000+ websites, 10.6 million downloads, and a 5.0 rating from 1,217 reviews on WordPress.org.
What Can You Do With Fonts Plugin?
Fonts Plugin lets you apply different fonts to different parts of your website. Choose one typeface for headings and another for body text, then adjust size, weight, colour, line height and letter spacing from the same screen. The live preview updates instantly, so you can see how a font looks on your own content before saving. The plugin works with every WordPress theme (Twenty Twenty-Five, GeneratePress, Elementor, and others) and requires no changes to your theme files.
What Fonts Are Available?
Fonts Plugin gives you three ways to get fonts onto your site.
• Google Fonts: over 1,900 typefaces, all free for personal and commercial use.
• Adobe Fonts (Typekit): connect your Adobe Creative Cloud subscription and use any typeface from your kit.
• Your own font files: upload in any standard format for brand fonts that aren’t in either library.
The opening of the plugin's own description. The full text, installation notes and changelog are on its WordPress.org page.