I have a MacBook Pro which came with macOS Mojave pre-installed. I have heard that macOS Catalina is releasing this fall.
I want to use the beta version of it. Where can I get it?
Public beta for macOS Catalina is now released by Apple. The same is available to download from Apple Beta Software Program website.
You can find handy guides for installing public betas here:
To download the macOS Catalina installer, select macOS tab on top of the page and under Get Started section click on enroll your Mac link.
If you're not on the Apple Developer Program and you want to test the beta OS, you'll have to wait until the public beta is available.
For macOS and iOS beta versions, the public beta dates have not been announced yet. You can go to the Apple Beta Signup. The production release date of Catalina hasn't been announced.