Is there any possibility to have filter on this page can be converted into the drop-down list

http://demo.virtualclone.in/ums/players/

Only a drop-down list will appear to select a specific category.

Many Thanks

You could override the function for your portfolio grid shortcode.
Then get the functionality from the portfolio-three-column.php (the one with the dropdown filter) and integrate it into your grid. If you struggle with this too let me know, I could help you with the filtering links in the sidebar solution… Have your FTP + admin credentials in a private reply.

$container.prev().find(".grid_filter_inline").find("li div");

in your common.js to this:

$container.parent().prev().find(".grid_filter_inline").find("li div");

and this:
$container.prev().find(".grid_filter_inline li div").removeClass("current_portfolio_item");
to this:
$container.parent().prev().find(".grid_filter_inline li div").removeClass("current_portfolio_item");

I also added this to your child theme’s css file so the items are full width in the column:

.portfolio_inline_filter ul li {
    display: block;
}

I would get rid of that FB sidebar so you have more room for the items now.