I want to make an tool that verify emails and check deliverables

I see a tool https://app.debounce.io/single-validation And I want to make a new tool for emails verification for my self...

If we put email here It will responce "Your email address is Invalid because it's Bounce." if email is invalid and Your email address is Safe to Send because it's Deliverable.  

attached screenshoot

I just need direction, I have knowldge of html, css, php (expert) and python(basic)... I don't want to learn design I just want to learn functionality ie

verify_email($email){
   return "valid email or invalid email";
}