I want to clean install the Catalina but there is
Macintosh HD - Data so I'm confused to deal with this extra partition.
macOS Catalina runs on a dedicated, read-only system volume called Macintosh HD. This volume is completely separate from all other data to help prevent the accidental overwriting of critical operating system files. Your files and data are stored in another volume named Macintosh HD - Data. In the Finder, both volumes appear as Macintosh HD. https://support.apple.com/en-us/HT210650
Then, these are the procedure.
- Click the Macintosh HD - Data (1) then click the minus above the Volume (2)
- Click the Macintosh HD (1) then click the Erase (2)
The rest is the same as usual.
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