Open Source macOS development is growing rapidly.
Open Source macOS development is growing rapidly.
MacOS parts are open source since it's built on BSD. If you need another OS for Apple devices, many Linux distributions and BSDs are available. You can create your own Linux version by installing Debian packages.
You can access the core of MacOS for free by using Darwin. You can obtain it directly from the Apple website or for a more user-friendly experience visit http://www.puredarwin.org. Keep in mind that you’ll need to create your own GUI or build one yourself, as some parts of MacOS aren’t open source and would require you to develop them yourself or locate open-source alternatives.
Also consider Elementary OS. Its design feels comparable to your objectives. Alternatively, explore any Linux distribution featuring a theme reminiscent of macOS. I'm not aiming to discourage you, but building an OS from the ground up is a significant project—perhaps joining a community that supports your preferred distro could be helpful.