"Uninstall" isn't the right word, but https://www.google.com/search?q=deactivate+cortana will surely help.
Make a careful note of your solution, since probably you'll have to repeat it twice a year if Microsoft does a feature update of Windows 10.
I have Cortana turned off on my laptop with Windows 10. Whenever I turn up the volume of my bluetooth headphones, Cortana turns on, the music turns off, and I hear "I can learn to understand you better if I can get familiar with the way you talk." How can I make Cortana just go away? Can I uninstall it?

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