Is Captcha available on free websites?

Website URL

goldenchambermusic.org

Error Message

(please share the FULL error message you see, if applicable)

Other Information

I would like to use Captcha to prevent potential malicious use of a webform. I see instructions here on using hCaptcha but they seem to require use of html code. I don’t see how to enter html code when using Website Builder on a free website. What should I do to provide security for my form?