How can I check an email’s legitimacy so I can…

I made a website and use formspree for the contacts page.

I got a couple of emails from people trying to contact me, but you never really know who you’re talking to…

In order to reply to these people I created a new disposable email for the website with very little perrsonal information about me, just use a common nickname, not my full name on the email, etc.

Is this enough to protect my privacy? Should I check these people out first, can I do any kind of background checks? Can I check the validity of their emails, I mean check if they weren’t made today for example?

EDIT: I’m getting downvoted, is my question inappropriate?

Found here