What model of Mac (and is it an Intel Mac or Apple Silicon -- or "M-series") Mac?
Is the "software named BlueJ" you are referring to the BlueJ Java integrated development environment (IDE)?
Assuming that you are talking about the BlueJ IDE and an Apple Silicon Mac:
- You won't be able to run macOS of any version as a virtual machine under Fusion. That's a limitation of the product.
- BlueJ is supported on Debian. I have a Debian 13 arm64 VM with 2 vCPUs, 4GB of memory, and a 20GB virtual hard drive. It's got over 9GB of space left after a minimal installation plus the BlueJ IDE arm64 6.0 software installation. BlueJ seems to run in that configuration -- although I have not tested it extensively with any kind of sizeable project.
Your mileage may vary., of course but I hope this is helpful in your decision making.
I'd steer clear of Tiny11 unless you have time on your hands. It's considered experimental and is unsupported by Microsoft (it is community/developer supported). Using it a a "daily driver" would open it up for spending more time dealing with issues than I have time to allot to it. If you do use Tiny11 on an Apple Silicon Mac, you may need to build it yourself using the tiny11builder scripts and an official Microsoft Windows 11 ARM ISO. Most things Windows tend to be still focused on Intel, regardless of the marketing of ARM-based Surface devices by Microsoft.