My Macbook Air has no system updates?

Hi Zoro,

Thanks for reaching out to us. 

I was able to find the following Apple KB article which covers the devices that are compatible with Catalina.
- macOS Catalina is compatible with these computers 

You can find a similar document for MacOS Big Sur as well. Your MacBook Air is not present on the lists so it will not be compatible with these OS'.

The similar page on macOS Monterey states that MacBook Air models Early 2015 or newer are compatible:
https://support.apple.com/en-gb/HT212551

The page on how to install macOS Monterey includes a link to the download:
https://support.apple.com/en-gb/HT212735

Good luck.

Thanks for sharing this information!