dropdown menu with directories

[Vin2020@]

Hi guys i'm new in this world.

I created a section with videos. I mean a link to display the video in my site.

near the video I created a dropdown menu. Well How can I create a dropdown menu withe the directories? for example: dir1 which contains video1 video2 etc. dir2 which contains video3 video4 etc.?

This is my code:

        <div class="dropdown">
        <button class="dropbtn"> search a video</button>
<div class="dropdown-content">

    <a href="root/holding.mp4"> holding</a>
    
    

    </div>
</div>

 

 

Thank's for your help