macOS Catalina (10.15) was a major release that ended support for legacy 32-bit apps in favor of 64-bit performance, brought Sidecar for iPad users, and replaced iTunes with Finder. The final, most stable version of this operating system is 10.15.7.
, you can do it directly through official Apple channels or via Terminal. This version is the final major release of Catalina, making it the most stable choice for older Macs. đź“Ą Official Download Link The safest way to get the installer is through the Mac App Store
Once you have the 8GB+ Install macOS Catalina.app in your Applications folder, insert a 16GB or larger USB drive (named "MyVolume" for this example). Then in Terminal, run:
Reference: Apple’s official “Create a bootable installer for macOS” article.
This is the official way to get the "Install macOS Catalina" app into your Applications folder: Direct Link : Open the macOS Catalina download page on the Mac App Store. Download icon Verification : Your Mac will open Software Update
softwareupdate --fetch-full-installer --full-installer-version 10.15.7
Download: The System Settings (or System Preferences) window will open, asking if you want to download macOS Catalina. Confirm the download.