Apple "signs" each version of macOS. As of mid-2023, Apple has stopped signing macOS Big Sur 11.0.1 for most Macs. This means:
How to Download macOS Big Sur 11.0.1 DMG MacOS Big Sur 11.0.1 (released in late 2020) marked a major shift for Apple, introducing a refined design, significant Safari updates, and support for the first M1 Macs. Whether you need to revive an older machine or create a bootable installer for troubleshooting, here is how you can find and download the macOS Big Sur 11.0.1 DMG. 1. Official Download Methods
Before you proceed, make sure your Mac meets the system requirements for macOS Big Sur:
This method gives you an official DMG, but it is not pure 11.0.1. To get exactly 11.0.1, you need advanced methods.