Using Google Fonts in Oracle APEX

1. Pick the font you want from Google Fonts. In this example, I picked Roboto, and you should add all the styles to the font family.

2. Add this CSS via Theme Roller->Custom CSS

@import url('https://fonts.googleapis.com/css2?family=Roboto:ital,wght@0,100;0,300;0,400;0,500;0,700;0,900;1,100;1,300;1,400;1,500;1,700;1,900&display=swap');
:root {
  --a-base-font-family: 'Roboto', sans-serif;
}

Add Google Font to CKEditor

Add two new fonts (Reenie Beanie, Open Sans) to C:\tomcat\webapps\i\libraries\ckeditor\3.6.4\config.js

CKEDITOR.editorConfig = function( config )
{
 // Define changes to default configuration here. For example:
 // config.language = 'fr';
 // config.uiColor = '#AADC6E';
 config.contentsCss = 'https://fonts.googleapis.com/css?family=Reenie+Beanie|Open+Sans';
    //the next line add the new font to the combobox in CKEditor
    config.font_names = 'Reenie Beanie/Reenie Beanie;Open Sans/Open Sans;' + config.font_names;
};

Add this to the html header section

<head>
<link href="https://fonts.googleapis.com/css?family=Reenie+Beanie|Open+Sans" rel="stylesheet" type="text/css">
</head>

Add this to the css style in your content

style="font-family: 'Reenie Beanie';"