Catalina
How to get macOS Catalina installed in an old Mac
macOS Catalina Patcher is an application that lets you install and run macOS 10.15 on unsupported hardware.
Apple releases MacOS Catalina 10.15.3 Beta 3 for testing
MacOS Catalina 10.15.3 beta 3 is out for testing and it mayย focus primarily on bug fixes, enhancements, and small improvements to MacOS Catalina, according to OSXDaily.