Hi Larry, on Mac, the menu bar is the bar at the top with the Apple logo, Firefox, Bookmarks, etc.

However, there is a limit to which versions of Firefox you can run on Mac OS X 10.11. I think you might already have the last compatible version. See: Firefox Mac OS X 10.9, 10.10 and 10.11 users move to Extended Support Release.

If the forum captured your OS version incorrectly, what version of Mac OS do you have?

Firefox 115 requires macOS 10.12, 10.13, 10.14 at minimum to run while Firefox 116.0 and later including 128.0 requires macOS 10.15 (ten.fifteen) at minimum to run.

So unless you can update to macOS 10.12 (ten.twelve) or later (to use Firefox 115 ESR) you will not be able to use Firefox 79.0 or later.