You have to edit source code and insert your BSV private key and address

Save File In BSV Blockchain

This is a minimal working script, and it doesn't display operation progress and errors.
You can see technical information in Developer Tools (in Firefox press Ctrl+Shift+K for console messages, or Ctrl+Shift+E for network connections).

in the topic: (optional)

Texts, pictures, and audio files shouldn't cause problems, but video files will cause problems. All above free sites refused to send files of 10Mb only, although BSV specification allows transactions of 1Gb.
TODO: try paid sites:
- local node (but system requirements are quite high)