my bank wants safari version 14

Safari is part of the operating system. If you keep your system up-to-date, Safari will be too. Your operating system is 10.13, 4 generations old. The ability to upgrade is based on the age of your device. Learn about software versions and hardware requirements at https://support.apple.com/en-us/HT211683.

If nothing else, you may be able to use a different browser (chrome, Firefox, etc.)

Back up your data, check your applications for compatibility, and depending on which Mac model you have, click on Mojave, Catalina, Big Sur, or Monterey. It needs to be at least a 2012 one to be upgraded.

Alternatively, use a browser such as Firefox to access the bank's website.

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