Is it possible to convert an .ELF file to an .ISO, please?

I use Open PS2 Loader to play games from an internal hard drive in my fat PS2. I want to add the homebrew game Geotron to the hard drive, too, but I can only find the game in .ELF format, not .ISO format.

Is it possible to convert the .ELF file to .ISO, or to download Geotron in .ISO format, or whatever?

https://www.psx-place.com/resources/geotron.414/

Thanks for any answers.