To make captcha working on your website, you have to get your own Site Key and Secret Key.
1) Login to your Google reCaptcha Admin Console via following link https://www.google.com/recaptcha/intro/v3.html
2) Click on plus sign to create and register new site
3) It’s important to select “reCAPTCHA v3” type while you are registering your site on “Register new site” page and fill your domain name where captcha will be used
4) Keys are generated after submit, simply copy and paste keys to appropriate inputs in Directory Settings