Please check this website to find out what is the latest macOS compatible with your old MacBook:
Mac OS Compatibility Guide Which versions of macOS does your Mac support?
macOS Compatibility for Mac Desktops
Which versions of macOS does your Mac Studio, Mac Pro, iMac, iMac Pro, or Mac mini support?
– Mac Studio
– Mac Pro
– iMac & iMac Pro
– Mac mini
macOS Compatibility for Mac Laptops Which versions of macOS does your MacBook Pro, MacBook Air, or MacBook support?
– MacBook Pro
– MacBook Air
macOS Compatibility for Rackmount Macs Which versions of macOS does your Xserve support?
iOS, iPadOS, watchOS Compatibility Which operating system versions does your iPhone, iPad, Apple Watch, or iPod support?
– Apple Watch
And just do a Google search to download ANY macOS you need, for example on the link below you can download macOS Big Sur for free on the Apple website:
#MacBookAir #macOS #Install
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