<form method="post" action="#" enctype="multipart/form-data" id="modPackage">
	<div id='MyDiv'>
    </div>
</form>

// Javascript

$.get("foo/foo.php", {
     // some data
  }, function(data){

        // Data return a string like "test1;test2;test3"
        let chaine = `<div><label> Title </label>`;
        const tab = ["test1", "test2", "test3", "test4", "test5"];

         tab.forEach(function(element){
            if(data.indexOf(element) != -1){
                chaine += `<input id='${element}' type='checkbox' name='test[]' value='${element}' style='width:26px;' checked />${element}`;

            } else {
               chaine += `<input id='${element}' type='checkbox' name='test[]' value='${element}' style='width:26px;' />${element}`;
            }
        });

        $("#MyDiv").html(chaine);
  }
);