How to highlight the current date in week view header scale bar

hi let me know how to highlight current date in week view like below.

Hello Sravan,
in order to change the view of the header please use the week_scale_date template:
https://docs.dhtmlx.com/scheduler/api__scheduler_week_scale_date_template.html
When you click on the event you can get the event object via the onClick event and take the actual date and the number of the day:

    var weekDay;
    scheduler.attachEvent("onClick", function (id, e){
    var date = e.path[2].ariaLabel;
    var formattedDate = new Date(date);
    weekDay = takeWeekDayNumber(formattedDate);
    scheduler.updateView();
    return true;
    });

After you get the actual date, you can change the header of the column via week_scale_date:

scheduler.templates.week_scale_date = function(date){  
var thisDay = takeWeekDayNumber(date);
if (weekDay && weekDay === thisDay) {
return `<div class="wrapper"><div 
class="circle">${takeWeekDayNumber(date)}</div>${format(date)}</div>`;
} else {  
return `<div class="wrapper"><div>${takeWeekDayNumber(date)} 
</div>${format(date)}</div>`;
}
};

Here is a related sample:
http://snippet.dhtmlx.com/5/fa55a2c9d