I went through all the main steps on this thread, and I have a Dell Inspiron 7386, and couldn't get headphone audio to work. I went through all the Dell driver updates as well to make sure all updates are made: https://www.dell.com/support/drivers.
What finally worked for me on Windows 11 is downloading Waves Maxx Audio Pro which helps enhance audio for Windows: https://apps.microsoft.com/detail/waves-maxxaudio-pro-for-dell-2019/9PJPPGG8TGVG?hl=en-us&gl=US&rtc=1
Within the Waves application window, there is a playback section to click on. Click on that and then try "Select Output Device" to Headphones, and then it worked finally! The Sound test option in the application helps to test the outputs, you will see that option in the bottom right of the application window.