If you own a Mac powered by Apple Silicon (such as the M1 processor), you no longer need to run your iPhone or iPad to run any of your favorite smartphone apps. As long as you’re running macOS 11 Big Sur or newer, you can download and install iPhone and iPad apps onto your Mac.

You'll first have to download it from Apple's App Store before you can run an iPhone or iPad app on your Mac or MacBook.

https://www.xclusivebyte.com/2020/11/how-to-run-iphone-and-ipad-apps-on-mac.html

macOS Big Sur ISO is used for various purposes. First, it can be used to install macOS Big Sur on computers that do not have internet access or to install the operating system on multiple computers without re-downloading network content. Secondly, the ISO image can be useful for creating a bootable USB drive that allows you to install macOS Big Sur on computers without an optical drive. Also, having an ISO image can be useful for backing up or restoring the system in case of crashes or malfunctions. Overall, macOS Big Sur ISO provides flexibility and convenience when installing, updating, and restoring macOS Big Sur.