JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script>
<form id="formCheckPassword">
    <input type="password"  name="password" id="password"/>
    <p id="passerror"></p>    
    <br>
    <input type="password"  name="cfmPassword" id="cfmPassword" disabled /><br>
    <input type="submit" value="submit" id="s"/>
 </form>

CSS

#passerror{
  
    color: red;
}

JavaScript

$(document).ready(function() {
			$("#s").click(function(event) {
      var passerror = "";
      var pass =  $.trim($("#password").val());
      if (pass == "") {
					passerror = "pass is required";
					$("#passerror").html(passerror);
					$("#passerror").show();
					event.preventDefault();
				} 
        if(pass!= cfmPassword)
        {
         display error message
        
        }
        else
        {
        
        }
   });
      
  $("#password").focusout(function(){
      var pwd=$("#password").val();
            var errorMessage = "";
    	        function isValidPassword(emailAddress) {
    	          var pattern = new RegExp(/^(?=.*\d)(?=.*[a-z])(?=.*[A-Z])[0-9a-zA-Z]{8,}$/);
    	          return pattern.test(emailAddress);
    	        };
    	        if (!isValidPassword(pwd.val())) {
    	          errorMessage = "<br />Please enter a valid email address";
    	          $("#error").html(errorMessage);
    	          $( "#error" ).show();
    	          event.preventDefault();
    	          
    	        }
    	       
    });     
		});