moms98 Said:
"Reinstall macOS: I have a 2018 MacAir and am giving it away. I used disk utility to erase and now trying to reinstall macOS. It had Monterey but only option to reinstall is Sierra and that fine. But when I try it says failed to download and go to purchase page. Any help? Just want to reinstall a functioning OS for my nephew."
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Properly Gving Away a Mac:
You should perform as instructed here, including the iCloud logout and backup creation: What to do Before you Sell, Dive Away, Trade In, or Recycle your Mac - Apple Support
How to Install:
Use a USB Bootable Installer: Create a Bootable Installer for macOS - Apple Support
Use Terminal to create one. If you do not use now o f these, then the latest compatible version will install: 13.4.1 (c). You would need to use terminal to create it. If you do don't have access to another Mac, then you'd need to install it to 13.4.1 (c), and then perform another fresh reinstall using the USB Bootable Installer for Monterey.