Can someone tell me how I can send data to MySQL database from a Div in a page without refreshing the page...using Ajax pls

Try studying how Ajax work. Visit w3schools.com or tutorialpoint

Make an ajax POST call to an endpoint, sending along the data you want to save to your mysql db, no?

create an event listener for the action you want to perform
eg

<button name="button" onclick="ajaxPost()">Post</button>

//create an ajax POST, using jquery
function ajaxPost(){
var post_value1; // assign it to whatever you need to
var post_value2; // assign it to whatever you need to

//create a separate "actual_database_sending_page.php" script in the same directory that will accept post parameters post_name1, post_name2
   $.post("actual_database_sending_page.php",
	{
	   post_name1: post_value1,
           post_name2: post_value2,
	}, function(data, status){
          // do whatever you want to do after running your php script, note 'data' is the output of "actual_database_sending_page.php"

          });
}

 

Check this out;

https://www.tutorialspoint.com/php/php_and_ajax.htm