macOS Catalina Patcher can be downloaded from http://dosdude1.com/catalina/

Before beginning, ensure your model is compatible under the "System Compatibility" tab on the page. Most 2008 to 2011 Macs are compatible with the patching tool.

macOS Catalina Patcher is a third-party tool developed by dosdude1, who has developed trusted, similar tools since macOS Sierra.