Theme typography customizations
In your admin panel, navigate to Appearance → Customize → Styling settings → Typography to access the typography customization settings. These settings allow you to select fonts, sizes and weights for headings and body text.
Disable Elementor default colors and fonts
The Elementor plugin automatically enabled it's own colors and fonts. It's recommended you disable those so that you have only true source for colors and fonts. Navigate to Elementor → Settings → General and enable the options highlighted in the screenshot below: