upgrade to newer version
how to upgrade newer / higher version from macOS Sierra version 10.12.6 ？
iMac 27″, macOS 10.12
Back up your data, check your applications for compatibility, click here, and depending on which iMac model you have, then on the download link for High Sierra, Mojave, Catalina, Big Sur, or Monterey.
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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