CloudFlare Captcha is increasingly used nowadays instead of Google ReCaptcha, as it is a more privacy-respecting option and also because it is more straight-forward. You don't have to tick any boxes or even photos of traffic lights, cars, etc...  which makes a smoother experience for your students.

It's a pity that Moodle only offers you the possibility to set up Google ReCaptcha, at least at the moment of writing this post (Moodle 4.5+). You can check if you go through Plugins/Authentication/manage authentication.

It would be great if someone could help with this. Thank you!!