I don’t see the erase all contents and settings

See the following from Erase all content and settings on Mac - Apple Support

Erase All Content and Settings is available only in macOS Monterey or later, and only on a Mac with Apple silicon or a Mac with the Apple T2 Security Chip. If this feature isn't available or doesn't work on your Mac:

• To restore factory settings, learn what to do before you sell, give away, or trade in your Mac.
• To erase, learn how to erase a Mac with Apple silicon or erase an Intel-based Mac.

If you see a message explaining that other volumes need to be erased before you can erase all content and settings, you might have used Boot Camp to install Microsoft Windows. In that case, use Boot Camp to remove Windows and its partition before continuing.

Does your Mac have a T2 chip? Erase all Content and Settings is dependent on encryption with the T2 chip (or an Apple Silicon Mac).

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