Hi abhi1015,
If the date textbox above the calendar is editable, then spy the textbox and use a Writer stage to put today's date in that textbox with the correct format.
If it is not editable then it is going to get tricky as in any date picker application using Blue Prism. In that case see which portion of the calendar when clicked inserts today's date and then spy that element and then click it. For eg; in some applications when you click on the "Today is Thursday..." at the bottom it inserts today's date. If that doesn't happen then you might need to spy each of the dates and correctly click on today's date or even check the javascript/vbscript code for this calendar in the 'View source' of the browser and see what exactly it is doing and try to mimic the same via Blue Prism. You might also get some hints on how to select the date based on the Attributes returned in the Application Modeller after spying the Calendar.