How to update the iOS on my MacBook Air Device OS X Yosemite Version 10.10.5 13 inch Early 2014

How to get old versions of macOS and verify what version this computer Qualifies to install.  For Best results use Safari to commence the download as Others may not work.

Safari will open a redirect and open the Apple Store where the download can commence.

macOS Catalina 10.15 hardware requirements

Notation - with 4 GB RAM - this computer will probably struggle to keep up with the demands of Catalina

macOS Mojave 10.14 hardware requirements

macOS High Sierra 10.13 hardware requirements

macOS Sierra 10.12 hardware requirements

OS X El Capitan - Technical Specifications

Make Time Machine Backup  is very useful and can be used to Revert to Previous Working macOS

Notation - Mojave is the Last version to support 32 bit applications / extensions and Drivers. Catalina, Big Sur & Monterey supports only 64 bit and there is no workaround.

Suggest using Go64 to find 32 bit application before attempting the upGrade. Some or many of the Application already installed may require an update or upGrades to 64 Bit Version

Back up your data, check your applications for compatibility, click here, and then on the download link for El Capitan, High Sierra, Mojave, Catalina, or Big Sur.

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

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