Hey Happybob123,
We see that you're unable to launch the iTunes app because it says that it's being updated, and we'd like to help!
Let's check if iTunes update progress shows under the App Store > Updates tab. If you don't see it there, then click on the Apple logo on the top left corner of your Mac > select About This Mac > Software Update.
If you see the iTunes update progress, see if you can cancel it. If you're unable to cancel the progress, try restarting your Mac and check again.
If the update was successfully canceled, try updating the iTunes app again by following the steps from here: Update to the latest version of iTunes
If none of the steps above worked, then boot your Mac into safe mode and try again: How to use safe mode on your Mac
We hope this helps!
Warm regards.