Can I upgrade Mojave 10.14.6 to a higher version

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 Catalina, Big Sur, or Monterey. If it's a 2010 or 2012 desktop Mac Pro, no.

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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