validate email address from string with jquery working function

HTML

<input type="email" id="emailfield" placeholder="Enter Email Address">
<button onclick="validate_email();">Check Email Address</button>

Scripts

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.6.0/jquery.min.js" referrerpolicy="no-referrer"></script>

Javascript

function validate_email() {
        var emailfield = $("#emailfield").val();
        var atpos = emailfield.indexOf("@");
        var dotpos = emailfield.lastIndexOf(".");
        console.log(atpos);

        // check the @ 1st
        if(atpos >= 1) {} else {
          alert("Email missing @");
          return false;
        }

        // check the dot pos
        if(dotpos >= 1) {} else {
          alert("Email missing .");
          return false;
        }
        alert("Email is valid");
      }