Hi @tommy1,
The password should be your computer administrator’s password. Etcher requires access to be granted in order to write at the block-level of the USB drive.
If you are running macOS, the following thread might be helpful in you finding the password needed: Etcher asks for a password on my MAC, does not recognize my admin password
If you are running another OS and not able to find the necessary password, let us know what OS you’re running and we can help guide you from there.