If you manage to obtain the DMG file, you can create a bootable installer using tools like DiskMaker X or Terminal commands.
After downloading the macOS Catalina installer, you should verify its integrity to ensure the file is complete and uncorrupted. Download Macos 10.15 Catalina Dmg File
Once finished, the "Install macOS Catalina" app will be in your Applications Microsoft Community Hub Method 2: Official Apple Support Downloads (Updates Only) If you manage to obtain the DMG file,
Use A Boy Soft Disk Geeker which is authenticated by Apple to download and create DMG files directly. Method 3: Third-Party Reliable Sources Download Macos 10.15 Catalina Dmg File
For advanced users, you can download the installer package directly using Apple’s softwareupdate command:
with at least 16 GB capacity.