Lightroom froze up on first try at de-noise.

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"The only response when clicking on mouse is a noise."

If you didn't see the Enhance Preview window:

then it sounds like the window is appearing off screen, on a second display, or underneath the main LR window.  It's a modal dialog, so if you click anywhere else within LR, LR will beep and the click is ignored.

Resetting preferences as @TheDigitalDog suggested is the easiest way to fix this.

Please post your System Information as Lightroom Classic (LrC) reports it. In LrC click on Help, then System Info, then Copy. Paste that information into a reply. Please present all information from first line down to and including Plug-in Info. Info after Plug-in info can be cut as that is just so much dead space to us non-Techs.

Try resetting your Lightroom preferences:
https://helpx.adobe.com/lightroom-classic/help/setting-preferences-lightroom.html
Also see: https://community.adobe.com/t5/lightroom-classic-discussions/important-steps-for-manually-resetting-preferences-omitted-from-help-article/td-p/12972518

Quit Lightroom Classic.
macOS: Press and hold the Shift + Option keys.
Windows: Press and hold the Shift + Alt keys.
While holding down the keys, launch Lightroom Classic.
When asked, select "Yes".