When it comes to loading fonts for your website, keep in mind that the font you choose will be displayed on all clients as long as the file from Google is accessible and the client supports this technology. It's important not to go overboard with loading multiple fonts, as this can significantly slow down page loading times due to the large size of font files.
In CSS, you have the ability to specify multiple fonts. If the primary font is not available, the browser will fallback to the second specified font. A good backup option is using a common font like "Arial" as the secondary choice, with something generic like "sans-serif" as a third option. This ensures that at least one readable font will be used on the webpage.
Even if none of the specified fonts are available, the client will always default to any font it deems suitable. This means that no text will ever go unnoticed or displayed incorrectly just because the CSS doesn't specify a specific font.