I can'r View Amazon Prime from my iMac, it says I don't have the most current Safari browser, and I do.

The current version of Safari is Safari 16.6 and is available only for macOS Monterey, Big Sur or Ventura.

The only information I found from Amazon Prime Video was the following: https://www.amazon.com/gp/help/customer/display.html?nodeId=GUVGB3QMQRYRERYW

What macOS version are you running (available from Apple menu > About This Mac). If it isn't one that supports the latest version of Safari, you may be able to use the current version of a 3rd party browser such as Chrome, depending on what macOS you have installed.

The latest version of Ventura is macOS 13.5 so you may want to update to that and it includes Safari 16.6 -- but I don't know why Amazon Prime would have a problem with what you have. Wouldn't hurt to upgrade to see if that helps.

See: Update macOS on Mac - Apple Support