cant update MacOS Big Sur on my mac air

Is it a 2013 or later MBA?

macOS Big Sur - Technical Specifications

General Requirements

• OS X 10.9 or later
• 4GB of memory
• 35.5GB available storage on macOS Sierra or later*
• Some features require an Apple ID; terms apply.
• Some features require a compatible internet service provider; fees may apply.

Mac Hardware Requirements

For details about your Mac model, click the Apple icon at the top left of your screen and choose About This Mac. These Mac models are compatible with macOS Big Sur:

• MacBook (2015 or later)
• MacBook Air (2013 or later)
• MacBook Pro (Late 2013 or later)
• Mac mini (2014 or later)
• iMac (2014 or later)
• iMac Pro (2017 or later)
• Mac Pro (2013 or later)

Learn about compatibility and how to identify your specific Mac model

Don't use FireFox or WaterFox for this link. it'll mess it up...

https://apps.apple.com/us/app/macos-big-sur/id1526878132?ls=1&mt=12

novelette Said:

"can't update MacOS Big Sur on my mac air: cant update MacOS Big SUR, need helpions.apple.com/thread/252357582"

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Try the Following, in the Order Provided:

A. Close Non-Responding Programs:

Go To: Finder Menu > Force Quit... > Select An Item Open that is "Not Responding"

B. Ty a New User:

Try creating a new user (for temporary use), seeing if you can install it through that.

C. Any Error Messages?

Take a screenshot of a message window, deleting personal info like names, emails, ect. Then reply with the screenshot as an attachment.

• Go Here: Take a Screenshot on your Mac - Apple Support
• Scroll to: How to capture a window or menu
• Proceed from there with a Screenshot:

Have you downloaded this &tried running it?

If so what exactly happens?

https://apps.apple.com/us/app/macos-big-sur/id1526878132?ls=1&mt=12

What exactly happens when you try?

How much Free Space do you have?

Have you tried the standalone installer I linked to, or just SW pd or what/how?