How to make a landing page contact form in php?

Question

Landing pages

I am making a landing without cms, just html+js+css, but the landing should have a feedback form and send a message to the mail.
How, from the point of view of security, is it correct to make a form for sending messages from the site to the mail?
By security, I mean not captcha, but anti-spam from my domain (the use of a script by attackers to send mail).

Answer 1

If I understood you correctly, then:
1. Use jquery validation, for example jqueryvalidation.org
2. Make a hidden field in the form, for example, with the name name, lastname, firstname, which bots usually fill out.
3. In the php script, we check whether the hidden fields are filled in, if yes, then this is a bot, if not, then we send the letter.