How do I install macOS on a 2019 MacBook Pro with forgotten password and internet Recovery mode?

Fern90s9df wrote:

Thank you, but nothing of that is working, and worse, i tried the solution in the next post and now i cant even exit from dfu mode :( Cannot install macOS on 2019 MacBook Pro - Apple Community

Perform an SMC Reset which should immediately power off the laptop.

You cannot boot from USB unless you previously had modified the system security settings to allow booting from USB. Once a T2 Mac is erased, it is impossible to modify the security settings to allow booting from USB because there are no longer any macOS admin user accounts to authenticate against.

About Startup Security Utility on a Mac with the Apple T2 Security Chip - Apple Support

When performing a DFU Firmware Revive or Restore, you must follow the instructions exactly. The instructions are confusing. Timing and pressing the correct keys is paramount. And you must have the USB cable (best to use Apple's USB-C charging cable which has no symbols on the connectors) must be connected to the DFU port on the "broken" T2 Mac.

How to revive or restore Mac firmware - Apple Support

You must use Recovery Mode (Command + R) or Internet Recovery Mode (Command + Option + R, or Command + Option + Shift + R) to reinstall macOS if USB booting was not previously enabled, or if you performed a DFU Firmware Restore (not sure about the Revive).

Edit: Forgot to include a link to the instructions for performing an SMC Reset for a T2 Mac which differs from the older Macs:

Reset the SMC of your Mac - Apple Support

Hi,

To install macOS using Internet Recovery, you need to boot your Mac into recovery mode and then use the built-in recovery tools to download and install the latest compatible macOS version. Specifically, you'll need to use the key combination Option-Command-R while starting up your Mac. 

Here's a more detailed breakdown:

1. Accessing Internet Recovery:

• Shutdown:
• Shut down your Mac completely. 
• Restart and Key Combination:
• Press and hold Option and Command keys simultaneously, then press the power button to turn on your Mac. 
• Release Keys:
• Continue holding the keys until you see a spinning globe and the message "Starting Internet Recovery". 
• Connect to WiFi (if necessary):
• If you're not using a wired internet connection, you'll be prompted to choose a Wi-Fi network. 

2. Installing macOS:

• Choose "Reinstall macOS":
• Once the recovery menu appears, select the option to "Reinstall macOS". 
• Follow On-Screen Instructions:
• Follow the prompts to select the disk where you want to install macOS (usually your startup disk) and proceed with the installation. 
• Wait for Completion:
• The installation process can take some time, so be patient and wait for it to complete. 
• First Launch:
• Once the installation is finished, your Mac will restart and you'll be able to log in and start using your new macOS installation. 

Important Considerations:

• Internet Connection:
• Internet Recovery requires a stable internet connection, either through Wi-Fi or Ethernet, says Apple Support. 
• Mac Compatibility:
• This method installs the latest macOS version that's compatible with your specific Mac model. 
• Alternative Key Combination:
• You can also use Option-Shift-Command-R to reinstall the original macOS version that came with your Mac, or the closest available version, according to Apple Support. 

Also se following article.

Use macOS Recovery on an Intel-based Mac – Apple Support (AU)