Can you upgrade software on a MacBook Air (11-inch, Early 2014)?

Back up your data, check your applications for compatibility, click here, and then on the download link for a newer OS; your computer's maximum one is Big Sur. If you're referring to something other than the OS, it depends on what that is.

Catalina and higher won't run 32-bit software; download and use Go64 as well as using the first link above.

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