Please, give me admin access.

Hi.

Please, place the font files to the folder /wp-content/themes/quattro-child/fonts/

Please, check now.

You are welcome)

1) To change the font to Arial, just replace Flama-Light in the file quattro-child/style.css https://take.ms/kUdFE

2) To add another font, that not included in google fonts, upload it to the quattro-child/fonts folder and import like this https://take.ms/Cbvez. And then rename font like in point 1). You can find information about @font-face with google search.

3) To return google fonts, delete or comment this code https://take.ms/GjS47 in quattro-child/functions.php and code from point 1).