My bank keeps saying I need to update my safari. I don't know how to do this. I can bank info on my phone but not my Mac

Chase requires Safari 16 or later (if you use Safari).

To upgrade Safari to Safari 16 or a later version you would need to upgrade your Mac to macOS 11 or a later version.

If you can’t or don’t want to upgrade, you may want to use a 3rd party internet browser that supports running their current version on your Mac. One option is Chrome: https://www.google.com/chrome/

If you reply with your Mac model (e.g.,  iMac, MacBook Pro, etc) and model year from Apple menu > About this Mac, someone here may be able to help with whether you can upgrade your macOS.

L2448 wrote:

I can't get in to my bank anymore for my info

This is clearly Chase Bank's problem to fix. They need to stop using the outdated and privacy-intrusive "user agent" query as the means to determine if a browser can handle their website, which was never a good idea to begin with.

If you are motivated to do so direct their attention to this excerpt from Apple's Safari Developer Documentation (emphasis added):

Important

Use feature detection to enable or disable functionality instead of relying on the name or version of the browser in the User Agent string. Learn how to detect available features on MDN…

The passage regarding feature detection in that document uses even stronger language:

"... this is a terrible practice that should be discouraged at all costs."

Unfortunately, Chase's continued use of that terrible practice leaves you out in the cold until they realize the error of their ways and correct it.

The workaround for end users who are unable to update their Macs to a newer macOS version is to use a different browser.

Consider Brave:

https://brave.com/

Firefox is a distant second choice:

https://www.mozilla.org/en-US/firefox/new/

The bottom line is that there is nothing wrong with your Mac's version of Safari, but that bank is using an outdated and ill-conceived method of determining browser requirements.