Cloudflare has a CAPTCHA called Turnstile. The captcha is free. It can be implemented as additional protection.

More: https://www.cloudflare.com/products/turnstile/

Quote

Cloudflare Turnstile delivers frustration-free, CAPTCHA-free web experiences to website visitors - with just a simple snippet of free code.

Previews:

 

There's already a suggestion for this 🙂