: View the file in a folder with "Large Icons" enabled to see a preview frame of the video.
: Search your "Saved Messages" or recent chats for "5021547738098041451" to find the original message. 1_5021547738098041451mp4
The filename "1_5021547738098041451mp4" follows the specific naming convention used by for downloaded media files. : View the file in a folder with
: Right-click the file → Properties → Details (Windows) to see if there is a contributing artist or original title. 1_5021547738098041451mp4
: You likely found this in your Telegram Desktop or Telegram Video folder.