how to update my mac 10.9.5

Back up your data, check your applications for compatibility, click here, and depending on which Mac model you have, then on the download link for El Capitan, High Sierra, Mojave, Catalina, Big Sur, or Monterey. If you encounter a specific issue, describe it in this thread.

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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