Updating from Sierra
How can I upgrade my mac from Sierra OSX 10.12.6 to the latest system suitable?
iMac 27″, macOS 10.12
Back up your data, check your applications for compatibility, click here, and then on the download link for a newer OS. A Mac running Sierra can be upgraded at least as far as High Sierra.
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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